diff --git a/.swiftlint.yml b/.swiftlint.yml
index 8d9ef1eb50c7..ec1bd3e0d268 100644
--- a/.swiftlint.yml
+++ b/.swiftlint.yml
@@ -119,3 +119,9 @@ custom_rules:
     message: "Using `LocalizedStringKey` is incompatible with our tooling and doesn't allow you to provide a hint/context comment for translators either. Please use `NSLocalizedString` instead, even with SwiftUI code."
     severity: error
     excluded: '.*Widgets/.*'
+
+  full_range_attributed_string_attribute:
+    name: "Full-Range Attributed String Attribute"
+    regex: '\.addAttributes?\([^\n]*range:\s*NS(MakeRange\(0,|Range\(location:\s*0,\s*length:)'
+    message: "Use `applyAttribute(_:value:)` or `applyAttributes(_:)` instead of manually constructing a full-range NSRange. Manual ranges are error-prone with emoji and other multi-code-unit characters."
+    severity: warning
diff --git a/Modules/Sources/FormattableContentKit/Ranges/FormattableNoticonRange.swift b/Modules/Sources/FormattableContentKit/Ranges/FormattableNoticonRange.swift
index f36bf68e87d3..fed0fafcd7f8 100644
--- a/Modules/Sources/FormattableContentKit/Ranges/FormattableNoticonRange.swift
+++ b/Modules/Sources/FormattableContentKit/Ranges/FormattableNoticonRange.swift
@@ -21,10 +21,10 @@ public class FormattableNoticonRange: FormattableContentRange {
         let shiftedRange = rangeShifted(by: shift)
         insertIcon(to: string, at: shiftedRange)
 
-        let longerRange = NSMakeRange(shiftedRange.location, shiftedRange.length + noticon.count)
+        let longerRange = NSMakeRange(shiftedRange.location, shiftedRange.length + noticon.utf16.count)
         apply(styles, to: string, at: longerRange)
 
-        return noticon.count
+        return noticon.utf16.count
     }
 
     func insertIcon(to string: NSMutableAttributedString, at shiftedRange: NSRange) {
diff --git a/Modules/Sources/WordPressKit/NonceRetrieval.swift b/Modules/Sources/WordPressKit/NonceRetrieval.swift
index 14e13b15d338..33f33c41143f 100644
--- a/Modules/Sources/WordPressKit/NonceRetrieval.swift
+++ b/Modules/Sources/WordPressKit/NonceRetrieval.swift
@@ -48,7 +48,7 @@ enum NonceRetrievalMethod {
 
     private func scrapNonceFromNewPost(html: String) -> String? {
         guard let regex = try? NSRegularExpression(pattern: "apiFetch.createNonceMiddleware\\(\\s*['\"](?<nonce>\\w+)['\"]\\s*\\)", options: []),
-            let match = regex.firstMatch(in: html, options: [], range: NSRange(location: 0, length: html.count)) else {
+            let match = regex.firstMatch(in: html, options: [], range: NSRange(location: 0, length: html.utf16.count)) else {
                 return nil
         }
         let nsrange = match.range(withName: "nonce")
diff --git a/Modules/Sources/WordPressKit/WordPressOrgXMLRPCValidator.swift b/Modules/Sources/WordPressKit/WordPressOrgXMLRPCValidator.swift
index 84e9b65dd5e6..e0f1b276d2e4 100644
--- a/Modules/Sources/WordPressKit/WordPressOrgXMLRPCValidator.swift
+++ b/Modules/Sources/WordPressKit/WordPressOrgXMLRPCValidator.swift
@@ -317,7 +317,7 @@ open class WordPressOrgXMLRPCValidator: NSObject {
 
         let matches = rsdURLRegExp.matches(in: html,
                                                    options: NSRegularExpression.MatchingOptions(),
-                                                   range: NSRange(location: 0, length: html.count))
+                                                   range: NSRange(location: 0, length: html.utf16.count))
         if matches.count <= 0 {
             return nil
         }
diff --git a/Modules/Sources/WordPressShared/Utility/RichContentFormatter.swift b/Modules/Sources/WordPressShared/Utility/RichContentFormatter.swift
index f23cf53b4ca1..7ca62af5ef6c 100644
--- a/Modules/Sources/WordPressShared/Utility/RichContentFormatter.swift
+++ b/Modules/Sources/WordPressShared/Utility/RichContentFormatter.swift
@@ -77,17 +77,17 @@ import WordPressSharedObjC
 
         content = RegEx.styleTags.stringByReplacingMatches(in: content,
                                                            options: .reportCompletion,
-                                                           range: NSRange(location: 0, length: content.count),
+                                                           range: NSRange(location: 0, length: content.utf16.count),
                                                            withTemplate: "")
 
         content = RegEx.scriptTags.stringByReplacingMatches(in: content,
                                                             options: .reportCompletion,
-                                                            range: NSRange(location: 0, length: content.count),
+                                                            range: NSRange(location: 0, length: content.utf16.count),
                                                             withTemplate: "")
 
         content = RegEx.gutenbergComments.stringByReplacingMatches(in: content,
                                                                    options: .reportCompletion,
-                                                                   range: NSRange(location: 0, length: content.count),
+                                                                   range: NSRange(location: 0, length: content.utf16.count),
                                                                    withTemplate: "")
 
         return content
@@ -111,23 +111,23 @@ import WordPressSharedObjC
         // Convert div tags to p tags
         content = RegEx.divTagsStart.stringByReplacingMatches(in: content,
                                                               options: .reportCompletion,
-                                                              range: NSRange(location: 0, length: content.count),
+                                                              range: NSRange(location: 0, length: content.utf16.count),
                                                               withTemplate: openPTag)
 
         content = RegEx.divTagsEnd.stringByReplacingMatches(in: content,
                                                             options: .reportCompletion,
-                                                            range: NSRange(location: 0, length: content.count),
+                                                            range: NSRange(location: 0, length: content.utf16.count),
                                                             withTemplate: closePTag)
 
         // Remove duplicate/redundant p tags.
         content = RegEx.pTagsStart.stringByReplacingMatches(in: content,
                                                             options: .reportCompletion,
-                                                            range: NSRange(location: 0, length: content.count),
+                                                            range: NSRange(location: 0, length: content.utf16.count),
                                                             withTemplate: openPTag)
 
         content = RegEx.pTagsEnd.stringByReplacingMatches(in: content,
                                                           options: .reportCompletion,
-                                                          range: NSRange(location: 0, length: content.count),
+                                                          range: NSRange(location: 0, length: content.utf16.count),
                                                           withTemplate: closePTag)
 
         content = filterNewLines(content)
@@ -141,11 +141,11 @@ import WordPressSharedObjC
         var ranges = [NSRange]()
         // We don't want to remove new lines from preformatted tag blocks,
         // so get the ranges of such blocks.
-        let matches = RegEx.preTags.matches(in: content, options: .reportCompletion, range: NSRange(location: 0, length: content.count))
+        let matches = RegEx.preTags.matches(in: content, options: .reportCompletion, range: NSRange(location: 0, length: content.utf16.count))
         if matches.count == 0 {
 
             // No blocks found, so we'll parse the whole string.
-            ranges.append(NSRange(location: 0, length: content.count))
+            ranges.append(NSRange(location: 0, length: content.utf16.count))
 
         } else {
 
@@ -161,7 +161,7 @@ import WordPressSharedObjC
                 location = match.range.location + match.range.length
             }
 
-            length = content.count - location
+            length = content.utf16.count - location
             ranges.append(NSRange(location: location, length: length))
         }
 
@@ -191,7 +191,7 @@ import WordPressSharedObjC
 
         content = RegEx.styleAttr.stringByReplacingMatches(in: content,
                                                            options: .reportCompletion,
-                                                           range: NSRange(location: 0, length: content.count),
+                                                           range: NSRange(location: 0, length: content.utf16.count),
                                                            withTemplate: "")
 
         return content
@@ -242,7 +242,7 @@ import WordPressSharedObjC
             mImageStr.replaceOccurrences(of: srcImgURLStr,
                                          with: modifiedURL.absoluteString,
                                          options: .literal,
-                                         range: NSRange(location: 0, length: imgElementStr.count))
+                                         range: NSRange(location: 0, length: imgElementStr.utf16.count))
 
             mContent.replaceCharacters(in: match.range, with: mImageStr as String)
         }
@@ -287,10 +287,9 @@ import WordPressSharedObjC
         }
 
         var content = string.trim()
-        let matches = RegEx.trailingBRTags.matches(in: content, options: .reportCompletion, range: NSRange(location: 0, length: content.count))
-        if let match = matches.first {
-            let index = content.index(content.startIndex, offsetBy: match.range.location)
-            content = String(content.prefix(upTo: index))
+        let matches = RegEx.trailingBRTags.matches(in: content, options: .reportCompletion, range: NSRange(location: 0, length: content.utf16.count))
+        if let match = matches.first, let range = Range(match.range, in: content) {
+            content = String(content[content.startIndex..<range.lowerBound])
         }
 
         return content
diff --git a/Modules/Sources/WordPressShared/Utility/String+RangeConveresion.swift b/Modules/Sources/WordPressShared/Utility/String+RangeConveresion.swift
index f5e7a1ce7fd1..77e737d6bacd 100644
--- a/Modules/Sources/WordPressShared/Utility/String+RangeConveresion.swift
+++ b/Modules/Sources/WordPressShared/Utility/String+RangeConveresion.swift
@@ -48,10 +48,10 @@ extension String {
     /// - Returns: the requested `Range<String.Index>`
     ///
     func range(from nsRange: NSRange) -> Range<String.Index> {
-        let lowerBound = index(startIndex, offsetBy: nsRange.location)
-        let upperBound = index(lowerBound, offsetBy: nsRange.length)
-
-        return lowerBound ..< upperBound
+        guard let range = Range(nsRange, in: self) else {
+            preconditionFailure("Invalid NSRange \(nsRange) for string of UTF-16 length \(utf16.count)")
+        }
+        return range
     }
 
     func range(fromUTF16NSRange utf16NSRange: NSRange) -> Range<String.Index> {
@@ -160,11 +160,7 @@ extension String {
     /// - Returns: the requested `NSRange`.
     ///
     func nsRange(from range: Range<String.Index>) -> NSRange {
-
-        let location = distance(from: startIndex, to: range.lowerBound)
-        let length = distance(from: range.lowerBound, to: range.upperBound)
-
-        return NSRange(location: location, length: length)
+        NSRange(range, in: self)
     }
 
     /// Converts a `Range<String.Index>` into an UTF16 NSRange.
@@ -190,7 +186,7 @@ extension String {
     /// Returns a NSRange with a starting location at the very end of the string
     ///
     func endOfStringNSRange() -> NSRange {
-        return NSRange(location: count, length: 0)
+        return NSRange(location: utf16.count, length: 0)
     }
 
     func indexFromLocation(_ location: Int) -> String.Index? {
diff --git a/Modules/Sources/WordPressShared/Utility/String+RegEx.swift b/Modules/Sources/WordPressShared/Utility/String+RegEx.swift
index 3a9e3270aeae..00d960edf737 100644
--- a/Modules/Sources/WordPressShared/Utility/String+RegEx.swift
+++ b/Modules/Sources/WordPressShared/Utility/String+RegEx.swift
@@ -16,7 +16,7 @@ extension String {
     public func replacingMatches(of regex: String, options: NSRegularExpression.Options = [], using block: (String, [String]) -> String) -> String {
 
         let regex = try! NSRegularExpression(pattern: regex, options: options)
-        let fullRange = NSRange(location: 0, length: count)
+        let fullRange = NSRange(location: 0, length: utf16.count)
         let matches = regex.matches(in: self, options: [], range: fullRange)
         var newString = self
 
@@ -49,7 +49,7 @@ extension String {
     ///
     public func matches(regex: String, options: NSRegularExpression.Options = []) -> [NSTextCheckingResult] {
         let regex = try! NSRegularExpression(pattern: regex, options: options)
-        let fullRange = NSRange(location: 0, length: count)
+        let fullRange = NSRange(location: 0, length: utf16.count)
 
         return regex.matches(in: self, options: [], range: fullRange)
     }
@@ -66,7 +66,7 @@ extension String {
     public func replacingMatches(of regex: String, with template: String, options: NSRegularExpression.Options = []) -> String {
 
         let regex = try! NSRegularExpression(pattern: regex, options: options)
-        let fullRange = NSRange(location: 0, length: count)
+        let fullRange = NSRange(location: 0, length: utf16.count)
 
         return regex.stringByReplacingMatches(in: self,
                                               options: [],
diff --git a/Modules/Sources/WordPressUI/Extensions/NSMutableAttributedString+Helpers.swift b/Modules/Sources/WordPressUI/Extensions/NSMutableAttributedString+Helpers.swift
index be4a7a9e3bd8..2289f8ccfe5f 100644
--- a/Modules/Sources/WordPressUI/Extensions/NSMutableAttributedString+Helpers.swift
+++ b/Modules/Sources/WordPressUI/Extensions/NSMutableAttributedString+Helpers.swift
@@ -5,10 +5,31 @@ import UIKit
 //
 extension NSMutableAttributedString {
 
+    /// Applies a single attribute to the entire string.
+    ///
+    /// Prefer this over manually constructing an `NSRange` with `NSMakeRange(0, …)`,
+    /// which is error-prone when mixing `String.count` (grapheme clusters) with
+    /// `NSRange` (UTF-16 code units).
+    ///
+    public func applyAttribute(_ key: NSAttributedString.Key, value: Any) {
+        // swiftlint:disable:next full_range_attributed_string_attribute
+        addAttribute(key, value: value, range: NSRange(location: 0, length: length))
+    }
+
+    /// Applies a collection of attributes to the entire string.
+    ///
+    /// Prefer this over manually constructing an `NSRange` with `NSMakeRange(0, …)`,
+    /// which is error-prone when mixing `String.count` (grapheme clusters) with
+    /// `NSRange` (UTF-16 code units).
+    ///
+    public func applyAttributes(_ attrs: [NSAttributedString.Key: Any]) {
+        // swiftlint:disable:next full_range_attributed_string_attribute
+        addAttributes(attrs, range: NSRange(location: 0, length: length))
+    }
+
     /// Applies the specified foreground color to the full length of the receiver.
     ///
     public func applyForegroundColor(_ color: UIColor) {
-        let range = NSRange(location: 0, length: length)
-        addAttribute(.foregroundColor, value: color, range: range)
+        applyAttribute(.foregroundColor, value: color)
     }
 }
diff --git a/Modules/Tests/WordPressSharedTests/RichContentFormatterTests.swift b/Modules/Tests/WordPressSharedTests/RichContentFormatterTests.swift
index e7d5c67030fe..87b365c85463 100644
--- a/Modules/Tests/WordPressSharedTests/RichContentFormatterTests.swift
+++ b/Modules/Tests/WordPressSharedTests/RichContentFormatterTests.swift
@@ -56,6 +56,48 @@ class RichContentFormatterTests: XCTestCase {
         XCTAssertTrue(range.location != NSNotFound)
     }
 
+    // MARK: - Emoji / Multi-byte Character Tests
+    //
+    // These tests verify that string operations work correctly with emoji
+    // and other characters where String.count (grapheme clusters) differs
+    // from String.utf16.count (UTF-16 code units used by NSRange).
+    // The family emoji 👨‍👩‍👧‍👦 is 1 grapheme cluster but 11 UTF-16 code units.
+
+    func testRemoveForbiddenTagsWithEmoji() {
+        let input = "<p>Hello 👨‍👩‍👧‍👦👨‍👩‍👧‍👦 World</p><script>evil</script>"
+        let expected = "<p>Hello 👨‍👩‍👧‍👦👨‍👩‍👧‍👦 World</p>"
+        let result = RichContentFormatter.removeForbiddenTags(input)
+        XCTAssertEqual(result, expected, "Script tags after emoji should be removed")
+    }
+
+    func testRemoveInlineStylesWithEmoji() {
+        let input = "<p>Hello 👨‍👩‍👧‍👦👨‍👩‍👧‍👦</p><p style=\"color:red;\">test</p>"
+        let expected = "<p>Hello 👨‍👩‍👧‍👦👨‍👩‍👧‍👦</p><p>test</p>"
+        let result = RichContentFormatter.removeInlineStyles(input)
+        XCTAssertEqual(result, expected, "Inline styles after emoji should be removed")
+    }
+
+    func testNormalizeParagraphsWithEmoji() {
+        let input = "<div>Hello 👨‍👩‍👧‍👦👨‍👩‍👧‍👦</div><div>test</div>"
+        let expected = "<p>Hello 👨‍👩‍👧‍👦👨‍👩‍👧‍👦</p><p>test</p>"
+        let result = RichContentFormatter.normalizeParagraphs(input)
+        XCTAssertEqual(result, expected, "Div-to-p conversion after emoji should work")
+    }
+
+    func testFilterNewLinesWithEmoji() {
+        let input = "<p>Hello 👨‍👩‍👧‍👦👨‍👩‍👧‍👦</p>\n<p>World</p>\n"
+        let expected = "<p>Hello 👨‍👩‍👧‍👦👨‍👩‍👧‍👦</p><p>World</p>"
+        let result = RichContentFormatter.filterNewLines(input)
+        XCTAssertEqual(result, expected, "Newlines after emoji should be filtered")
+    }
+
+    func testRemoveTrailingBreakTagsWithEmoji() {
+        let input = "<p>Hello 👨‍👩‍👧‍👦👨‍👩‍👧‍👦 World</p><br><br> "
+        let expected = "<p>Hello 👨‍👩‍👧‍👦👨‍👩‍👧‍👦 World</p>"
+        let result = RichContentFormatter.removeTrailingBreakTags(input)
+        XCTAssertEqual(result, expected, "Trailing BR tags after emoji should be removed")
+    }
+
     func testFormatVideoTags() {
         let str1 = "<p>Some text.</p><video></video><p>Some text.</p>"
         let sanitizedStr1 = RichContentFormatter.formatVideoTags(str1) as NSString
diff --git a/Modules/Tests/WordPressSharedTests/StringRangeConversionTests.swift b/Modules/Tests/WordPressSharedTests/StringRangeConversionTests.swift
new file mode 100644
index 000000000000..7bb6cc798846
--- /dev/null
+++ b/Modules/Tests/WordPressSharedTests/StringRangeConversionTests.swift
@@ -0,0 +1,123 @@
+import Testing
+import Foundation
+import UIKit
+
+@testable import WordPressShared
+
+struct StringRangeConversionTests {
+
+    // MARK: - range(from nsRange: NSRange) -> Range<String.Index>
+
+    @Test("range(from:) converts NSRange correctly for ASCII strings")
+    func rangeFromNSRangeASCII() {
+        let string = "Hello, world!"
+        let nsRange = NSRange(location: 7, length: 5)
+        let range = string.range(from: nsRange)
+        #expect(String(string[range]) == "world")
+    }
+
+    @Test("range(from:) converts NSRange correctly for strings with emoji")
+    func rangeFromNSRangeWithEmoji() {
+        // 👨‍👩‍👧‍👦 is 1 grapheme cluster but 11 UTF-16 code units
+        let string = "👨‍👩‍👧‍👦 Hello"
+        let nsRange = NSRange(location: 12, length: 5) // UTF-16 offset past emoji + space
+        let range = string.range(from: nsRange)
+        #expect(String(string[range]) == "Hello")
+    }
+
+    @Test("range(from:) handles multi-byte characters in the middle")
+    func rangeFromNSRangeWithEmojiInMiddle() {
+        // "AB👨‍👩‍👧‍👦CD" — 'A'=1, 'B'=1, emoji=11, 'C'=1, 'D'=1 UTF-16 units
+        let string = "AB👨‍👩‍👧‍👦CD"
+        let nsRange = NSRange(location: 13, length: 2) // "CD"
+        let range = string.range(from: nsRange)
+        #expect(String(string[range]) == "CD")
+    }
+
+    // MARK: - nsRange(from range: Range<String.Index>) -> NSRange
+
+    @Test("nsRange(from:) produces correct UTF-16 NSRange for ASCII strings")
+    func nsRangeFromSwiftRangeASCII() {
+        let string = "Hello, world!"
+        let swiftRange = string.range(of: "world")!
+        let nsRange = string.nsRange(from: swiftRange)
+        #expect(nsRange.location == 7)
+        #expect(nsRange.length == 5)
+    }
+
+    @Test("nsRange(from:) produces correct UTF-16 NSRange with emoji")
+    func nsRangeFromSwiftRangeWithEmoji() {
+        // 👨‍👩‍👧‍👦 is 1 grapheme cluster but 11 UTF-16 code units
+        let string = "👨‍👩‍👧‍👦 Hello"
+        let swiftRange = string.range(of: "Hello")!
+        let nsRange = string.nsRange(from: swiftRange)
+        // "Hello" starts at UTF-16 offset 12 (11 for emoji + 1 for space)
+        #expect(nsRange.location == 12)
+        #expect(nsRange.length == 5)
+    }
+
+    @Test("nsRange(from:) result works correctly with NSAttributedString")
+    func nsRangeFromSwiftRangeWorksWithAttributedString() {
+        let string = "👨‍👩‍👧‍👦 Bold text"
+        let swiftRange = string.range(of: "Bold")!
+        let nsRange = string.nsRange(from: swiftRange)
+        let attributed = NSMutableAttributedString(string: string)
+        // This should not crash — if nsRange used grapheme offsets, this would
+        // produce an out-of-bounds range for NSAttributedString
+        attributed.addAttribute(.font, value: UIFont.boldSystemFont(ofSize: 14), range: nsRange)
+        let attrs = attributed.attributes(at: nsRange.location, effectiveRange: nil)
+        #expect(attrs[.font] != nil)
+    }
+
+    // MARK: - nsRange(of:) -> NSRange?
+
+    @Test("nsRange(of:) produces correct UTF-16 NSRange for substring after emoji")
+    func nsRangeOfSubstringAfterEmoji() {
+        let string = "👨‍👩‍👧‍👦 world"
+        let nsRange = string.nsRange(of: "world")
+        #expect(nsRange != nil)
+        #expect(nsRange!.location == 12) // 11 for emoji + 1 for space
+        #expect(nsRange!.length == 5)
+    }
+
+    @Test("nsRange(of:) result can be used with NSRegularExpression range")
+    func nsRangeOfWorksWithRegex() {
+        let string = "🎉 test@example.com"
+        // Find "test@example.com" via nsRange(of:) and verify it matches UTF-16 offsets
+        let nsRange = string.nsRange(of: "test@example.com")!
+        let nsString = string as NSString
+        let extracted = nsString.substring(with: nsRange)
+        #expect(extracted == "test@example.com")
+    }
+
+    // MARK: - endOfStringNSRange()
+
+    @Test("endOfStringNSRange() uses UTF-16 count for emoji strings")
+    func endOfStringNSRangeWithEmoji() {
+        // 👨‍👩‍👧‍👦 is 1 grapheme cluster but 11 UTF-16 code units
+        let string = "👨‍👩‍👧‍👦"
+        let nsRange = string.endOfStringNSRange()
+        #expect(nsRange.location == 11) // UTF-16 count, not grapheme count (1)
+        #expect(nsRange.length == 0)
+    }
+
+    @Test("endOfStringNSRange() is consistent with NSString length")
+    func endOfStringNSRangeConsistentWithNSString() {
+        let string = "Hello 🌍 World 👨‍👩‍👧‍👦!"
+        let nsRange = string.endOfStringNSRange()
+        let nsString = string as NSString
+        #expect(nsRange.location == nsString.length)
+    }
+
+    // MARK: - Round-trip consistency
+
+    @Test("NSRange → Range → NSRange round-trip preserves values with emoji")
+    func roundTripWithEmoji() {
+        let string = "👨‍👩‍👧‍👦 Hello 🌍 World"
+        let original = NSRange(location: 12, length: 5) // "Hello"
+        let swiftRange = string.range(from: original)
+        let roundTripped = string.nsRange(from: swiftRange)
+        #expect(roundTripped.location == original.location)
+        #expect(roundTripped.length == original.length)
+    }
+}
diff --git a/Modules/Tests/WordPressUIUnitTests/Extensions/NSMutableAttributedStringHelpersTests.swift b/Modules/Tests/WordPressUIUnitTests/Extensions/NSMutableAttributedStringHelpersTests.swift
new file mode 100644
index 000000000000..7b26428b1e63
--- /dev/null
+++ b/Modules/Tests/WordPressUIUnitTests/Extensions/NSMutableAttributedStringHelpersTests.swift
@@ -0,0 +1,60 @@
+import Testing
+import UIKit
+
+@testable import WordPressUI
+
+struct NSMutableAttributedStringHelpersTests {
+
+    // MARK: - applyAttribute(_:value:)
+
+    @Test("applyAttribute covers the full string including emoji")
+    func applyAttributeWithEmoji() {
+        // 👨‍👩‍👧‍👦 is 1 grapheme cluster but 11 UTF-16 code units
+        let string = NSMutableAttributedString(string: "Hello 👨‍👩‍👧‍👦 World")
+        string.applyAttribute(.foregroundColor, value: UIColor.red)
+
+        var effectiveRange = NSRange()
+        let value = string.attribute(.foregroundColor, at: 0, effectiveRange: &effectiveRange)
+
+        #expect(value != nil)
+        #expect(effectiveRange.location == 0)
+        #expect(effectiveRange.length == string.length)
+    }
+
+    // MARK: - applyAttributes(_:)
+
+    @Test("applyAttributes covers the full string including emoji")
+    func applyAttributesWithEmoji() {
+        let string = NSMutableAttributedString(string: "👨‍👩‍👧‍👦👨‍👩‍👧‍👦 テスト")
+        let attrs: [NSAttributedString.Key: Any] = [
+            .foregroundColor: UIColor.blue,
+            .font: UIFont.systemFont(ofSize: 14)
+        ]
+        string.applyAttributes(attrs)
+
+        var colorRange = NSRange()
+        let color = string.attribute(.foregroundColor, at: 0, effectiveRange: &colorRange)
+
+        var fontRange = NSRange()
+        let font = string.attribute(.font, at: 0, effectiveRange: &fontRange)
+
+        #expect(color != nil)
+        #expect(colorRange.length == string.length)
+        #expect(font != nil)
+        #expect(fontRange.length == string.length)
+    }
+
+    // MARK: - applyForegroundColor(_:)
+
+    @Test("applyForegroundColor covers the full string including emoji")
+    func applyForegroundColorWithEmoji() {
+        let string = NSMutableAttributedString(string: "🌍 Hello 🌍")
+        string.applyForegroundColor(.green)
+
+        var effectiveRange = NSRange()
+        let value = string.attribute(.foregroundColor, at: 0, effectiveRange: &effectiveRange)
+
+        #expect(value as? UIColor == .green)
+        #expect(effectiveRange.length == string.length)
+    }
+}
diff --git a/Sources/WordPressAuthenticator/Helpers/UnifiedAuth/ViewRelated/2FA/TwoFAViewController.swift b/Sources/WordPressAuthenticator/Helpers/UnifiedAuth/ViewRelated/2FA/TwoFAViewController.swift
index d28708fa6a7d..138a00aa99af 100644
--- a/Sources/WordPressAuthenticator/Helpers/UnifiedAuth/ViewRelated/2FA/TwoFAViewController.swift
+++ b/Sources/WordPressAuthenticator/Helpers/UnifiedAuth/ViewRelated/2FA/TwoFAViewController.swift
@@ -599,7 +599,6 @@ private extension TwoFAViewController {
     ///
     func configureForAccessibility() {
         view.accessibilityElements = [
-            codeField as Any,
             tableView as Any,
             submitButton as Any
         ]
diff --git a/Sources/WordPressAuthenticator/Helpers/UnifiedAuth/ViewRelated/Password/PasswordViewController.swift b/Sources/WordPressAuthenticator/Helpers/UnifiedAuth/ViewRelated/Password/PasswordViewController.swift
index bdeb49a8e5db..37ac8a7fd52c 100644
--- a/Sources/WordPressAuthenticator/Helpers/UnifiedAuth/ViewRelated/Password/PasswordViewController.swift
+++ b/Sources/WordPressAuthenticator/Helpers/UnifiedAuth/ViewRelated/Password/PasswordViewController.swift
@@ -523,7 +523,6 @@ private extension PasswordViewController {
     ///
     func configureForAccessibility() {
         view.accessibilityElements = [
-            passwordField as Any,
             tableView as Any,
             submitButton as Any
         ]
diff --git a/Sources/WordPressAuthenticator/Helpers/UnifiedAuth/ViewRelated/SiteAddress/SiteAddressViewController.swift b/Sources/WordPressAuthenticator/Helpers/UnifiedAuth/ViewRelated/SiteAddress/SiteAddressViewController.swift
index 33ac6331b4e6..544b19c97637 100644
--- a/Sources/WordPressAuthenticator/Helpers/UnifiedAuth/ViewRelated/SiteAddress/SiteAddressViewController.swift
+++ b/Sources/WordPressAuthenticator/Helpers/UnifiedAuth/ViewRelated/SiteAddress/SiteAddressViewController.swift
@@ -141,7 +141,6 @@ final class SiteAddressViewController: LoginViewController {
     ///
     private func configureForAccessibility() {
         view.accessibilityElements = [
-            siteURLField as Any,
             tableView as Any,
             submitButton as Any
         ]
diff --git a/Sources/WordPressAuthenticator/Helpers/UnifiedAuth/ViewRelated/SiteAddress/SiteCredentialsViewController.swift b/Sources/WordPressAuthenticator/Helpers/UnifiedAuth/ViewRelated/SiteAddress/SiteCredentialsViewController.swift
index 89b4d15d8eaa..232637b15952 100644
--- a/Sources/WordPressAuthenticator/Helpers/UnifiedAuth/ViewRelated/SiteAddress/SiteCredentialsViewController.swift
+++ b/Sources/WordPressAuthenticator/Helpers/UnifiedAuth/ViewRelated/SiteAddress/SiteCredentialsViewController.swift
@@ -133,7 +133,6 @@ final class SiteCredentialsViewController: LoginViewController {
     ///
     private func configureForAccessibility() {
         view.accessibilityElements = [
-            usernameField as Any,
             tableView as Any,
             submitButton as Any
         ]
diff --git a/Tests/KeystoneTests/Tests/Features/JetpackScanThreatContextTests.swift b/Tests/KeystoneTests/Tests/Features/JetpackScanThreatContextTests.swift
new file mode 100644
index 000000000000..c72014c7a2a1
--- /dev/null
+++ b/Tests/KeystoneTests/Tests/Features/JetpackScanThreatContextTests.swift
@@ -0,0 +1,48 @@
+import XCTest
+@testable import WordPressKit
+@testable import WordPress
+
+final class JetpackScanThreatContextTests: XCTestCase {
+
+    private let config = JetpackThreatContext.JetpackThreatContextRendererConfig(
+        numberAttributes: [.foregroundColor: UIColor.gray],
+        highlightedNumberAttributes: [.foregroundColor: UIColor.red],
+        contentsAttributes: [.foregroundColor: UIColor.label],
+        highlightedContentsAttributes: [.foregroundColor: UIColor.label],
+        highlightedSectionAttributes: [.backgroundColor: UIColor.yellow]
+    )
+
+    /// Regression test: file contents with multi-byte characters (emoji, CJK)
+    /// should not crash or produce incorrect attributed strings.
+    /// Previously, `String.count` was used instead of `String.utf16.count`
+    /// for NSRange construction, which could produce out-of-bounds ranges.
+    func testAttributedStringWithMultiByteContents() {
+        let lines: [JetpackThreatContext.ThreatContextLine] = [
+            .init(lineNumber: 1, contents: "<?php // 👨‍👩‍👧‍👦 emoji test", highlights: nil),
+            .init(lineNumber: 2, contents: "echo '日本語テスト';", highlights: nil),
+        ]
+
+        let context = JetpackThreatContext(with: lines)
+        let attributed = context.attributedString(with: config)
+
+        XCTAssertNotNil(attributed, "Should produce a valid attributed string")
+
+        // Verify the attributed string contains both lines' content
+        let fullText = attributed!.string
+        XCTAssertTrue(fullText.contains("👨‍👩‍👧‍👦"), "Should contain emoji")
+        XCTAssertTrue(fullText.contains("日本語テスト"), "Should contain CJK text")
+    }
+
+    /// Verify that highlighted lines with multi-byte content don't crash.
+    func testAttributedStringWithMultiByteHighlightedContents() {
+        let lines: [JetpackThreatContext.ThreatContextLine] = [
+            .init(lineNumber: 1, contents: "<?php // 👨‍👩‍👧‍👦 emoji", highlights: nil),
+            .init(lineNumber: 2, contents: "eval('malicious');", highlights: [NSRange(location: 0, length: 4)]),
+        ]
+
+        let context = JetpackThreatContext(with: lines)
+        let attributed = context.attributedString(with: config)
+
+        XCTAssertNotNil(attributed, "Should produce a valid attributed string with highlights")
+    }
+}
diff --git a/Tests/KeystoneTests/Tests/Features/Notifications/FormattableContentGroupTests.swift b/Tests/KeystoneTests/Tests/Features/Notifications/FormattableContentGroupTests.swift
index dce60ea28a8d..ace406c0dd0b 100644
--- a/Tests/KeystoneTests/Tests/Features/Notifications/FormattableContentGroupTests.swift
+++ b/Tests/KeystoneTests/Tests/Features/Notifications/FormattableContentGroupTests.swift
@@ -50,6 +50,53 @@ final class FormattableContentGroupTests: CoreDataTestCase {
         XCTAssertNil(obtainedBlock)
     }
 
+    // MARK: - pingbackReadMoreGroup
+
+    func testPingbackReadMoreGroupLinkRangeCoversFullText() {
+        let url = URL(string: "https://example.com")!
+        let group = BodyContentGroup.pingbackReadMoreGroup(for: url)
+        let block = group.blocks.first as! FormattableTextContent
+        let text = block.text!
+
+        // Find the link range (the NotificationContentRange with kind .link)
+        let linkRange = block.ranges.first { $0.kind == .link }!
+
+        // The range must cover the full string using UTF-16 counts,
+        // which is what NSAttributedString expects.
+        XCTAssertEqual(linkRange.range.location, 0)
+        XCTAssertEqual(linkRange.range.length, text.utf16.count)
+    }
+
+    /// Regression test: building a full-text link range with `String.count`
+    /// instead of `String.utf16.count` produces the wrong NSRange when the
+    /// text contains multi-byte characters (e.g. emoji). The range must use
+    /// UTF-16 counts because NSAttributedString is backed by UTF-16.
+    func testFullTextLinkRangeWithEmojiUsesUTF16Count() {
+        // 👨‍👩‍👧‍👦 is 1 grapheme cluster but 11 UTF-16 code units.
+        let text = "👨‍👩‍👧‍👦 ソースの投稿を読む"
+        let url = URL(string: "https://example.com")!
+
+        let textRange = NSRange(location: 0, length: text.utf16.count)
+        var properties = NotificationContentRange.Properties(range: textRange)
+        properties.url = url
+
+        let linkRange = NotificationContentRange(kind: .link, properties: properties)
+
+        // The range must match NSAttributedString's length (UTF-16 based)
+        let attributed = NSMutableAttributedString(string: text)
+        XCTAssertEqual(linkRange.range.length, attributed.length,
+                       "Link range length should equal NSAttributedString.length (UTF-16)")
+
+        // Applying the range to an attributed string must not crash
+        attributed.addAttribute(.link, value: url, range: linkRange.range)
+
+        // Verify the link covers the full string
+        var effectiveRange = NSRange()
+        let value = attributed.attribute(.link, at: 0, effectiveRange: &effectiveRange)
+        XCTAssertNotNil(value)
+        XCTAssertEqual(effectiveRange.length, attributed.length)
+    }
+
     private func mockContent() throws -> FormattableTextContent {
         let text = try mockActivity()["text"] as? String ?? ""
         return FormattableTextContent(text: text, ranges: [], actions: [])
diff --git a/Tests/KeystoneTests/Tests/Features/Notifications/FormattableNotIconTests.swift b/Tests/KeystoneTests/Tests/Features/Notifications/FormattableNotIconTests.swift
index b0c616ca4bbb..8d18c86a2134 100644
--- a/Tests/KeystoneTests/Tests/Features/Notifications/FormattableNotIconTests.swift
+++ b/Tests/KeystoneTests/Tests/Features/Notifications/FormattableNotIconTests.swift
@@ -34,6 +34,35 @@ final class FormattableNotIconTests: XCTestCase {
         XCTAssertEqual(subject?.value, Constants.icon)
     }
 
+    // MARK: - apply(_:to:withShift:)
+
+    func testApplyReturnsUTF16ShiftForMultiByteNoticon() {
+        // 👨‍👩‍👧‍👦 is 1 grapheme cluster but 11 UTF-16 code units.
+        // The noticon string is value + " ", so 12 UTF-16 code units total.
+        // With the old .count code, the shift would have been 2 (1 emoji + 1 space).
+        let familyEmoji = "👨‍👩‍👧‍👦"
+        let noticonRange = FormattableNoticonRange(value: familyEmoji, range: NSRange(location: 0, length: 0))
+
+        let baseText = "Hello World"
+        let string = NSMutableAttributedString(string: baseText)
+
+        let styles = SnippetsContentStyles(rangeStylesMap: [
+            .noticon: [.foregroundColor: UIColor.red]
+        ])
+
+        let shift = noticonRange.apply(styles, to: string, withShift: 0)
+
+        // The noticon is familyEmoji + " " = 12 UTF-16 code units
+        let expectedShift = (familyEmoji + " ").utf16.count
+        XCTAssertEqual(shift, expectedShift, "Shift should equal the UTF-16 count of the noticon, not the grapheme cluster count")
+
+        // Verify styles were applied to the full noticon range
+        var effectiveRange = NSRange()
+        let color = string.attribute(.foregroundColor, at: 0, effectiveRange: &effectiveRange)
+        XCTAssertNotNil(color)
+        XCTAssertEqual(effectiveRange.length, expectedShift, "Style should cover the full UTF-16 range of the inserted noticon")
+    }
+
     private func mockProperties() -> NotificationContentRange.Properties {
         return NotificationContentRange.Properties(range: Constants.range)
     }
diff --git a/Tests/WordPressKitTests/CoreAPITests/WordPressOrgXMLRPCValidatorTests.swift b/Tests/WordPressKitTests/CoreAPITests/WordPressOrgXMLRPCValidatorTests.swift
index a66c00d7abd1..c39e20266ec3 100644
--- a/Tests/WordPressKitTests/CoreAPITests/WordPressOrgXMLRPCValidatorTests.swift
+++ b/Tests/WordPressKitTests/CoreAPITests/WordPressOrgXMLRPCValidatorTests.swift
@@ -368,6 +368,76 @@ final class WordPressOrgXMLRPCValidatorTests: XCTestCase {
         wait(for: [failure], timeout: 0.3)
     }
 
+    // Regression test: emoji in HTML before the RSD link caused the regex
+    // range to be too short because `String.count` (grapheme clusters) was
+    // used instead of `String.utf16.count` (UTF-16 code units for NSRange).
+    func testSuccessWithRSDLinkAfterEmoji() throws {
+        let responseInvalidPath = try XCTUnwrap(xmlrpcResponseInvalidPath)
+        stub(condition: isHost("www.apple.com") && isPath("/blog/xmlrpc.php")) { _ in
+            return fixture(filePath: responseInvalidPath, status: 403, headers: nil)
+        }
+
+        stub(condition: isHost("www.apple.com") && isPath("/blog")) { _ in
+            // The family emoji 👨‍👩‍👧‍👦 is 1 grapheme cluster but 11 UTF-16 code units.
+            // Placing many of them *before* the RSD link tag means the gap between
+            // String.count and utf16.count is large enough that an NSRange built
+            // with String.count will be too short to cover the link tag.
+            let emoji = String(repeating: "👨‍👩‍👧‍👦", count: 50)
+            let html = """
+                <!DOCTYPE html>
+                <html>
+                    <head>
+                        <title>\(emoji)</title>
+                        <link rel="EditURI" type="application/rsd+xml" title="RSD" href="https://www.apple.com/blog/rsd" />
+                    </head>
+                    <body>hello world</body>
+                </html>
+                """
+            return HTTPStubsResponse(data: html.data(using: .utf8)!, statusCode: 200, headers: nil)
+        }
+
+        stub(condition: isAbsoluteURLString("https://www.apple.com/blog/rsd")) { _ in
+            let xml = """
+                <?xml version="1.0" encoding="UTF-8"?><rsd version="1.0" xmlns="http://archipelago.phrasewise.com/rsd">
+                    <service>
+                        <engineName>WordPress</engineName>
+                        <engineLink>https://wordpress.org/</engineLink>
+                        <homePageLink>https://developer.wordpress.org</homePageLink>
+                        <apis>
+                            <api name="WordPress" blogID="1" preferred="true" apiLink="https://www.apple.com/blog-xmlrpc.php" />
+                        </apis>
+                    </service>
+                </rsd>
+                """
+            return HTTPStubsResponse(
+                data: xml.data(using: .utf8)!,
+                statusCode: 200,
+                headers: ["Content-Type": "application/xml"]
+            )
+        }
+
+        let responseList = try XCTUnwrap(
+            OHPathForFileInBundle("xmlrpc-response-list-methods.xml", Bundle.coreAPITestsBundle)
+        )
+        stub(condition: isHost("www.apple.com") && isPath("/blog-xmlrpc.php")) { _ in
+            fixture(
+                filePath: responseList,
+                status: 200,
+                headers: ["Content-Type": "application/xml"]
+            )
+        }
+
+        let success = self.expectation(description: "success result")
+        let validator = WordPressOrgXMLRPCValidator()
+        validator.guessXMLRPCURLForSite("https://www.apple.com/blog", userAgent: "test/1.0", success: {
+            XCTAssertEqual($0.absoluteString, "https://www.apple.com/blog-xmlrpc.php")
+            success.fulfill()
+        }) {
+            XCTFail("Unexpected result: \($0)")
+        }
+        wait(for: [success], timeout: 0.3)
+    }
+
     let xmlrpcResponseInvalidPath = OHPathForFileInBundle(
         "xmlrpc-response-invalid.html",
         Bundle.coreAPITestsBundle
diff --git a/WordPress/Classes/Extensions/NSAttributedString+StyledHTML.swift b/WordPress/Classes/Extensions/NSAttributedString+StyledHTML.swift
index 10727ac592c3..c2605a0804df 100644
--- a/WordPress/Classes/Extensions/NSAttributedString+StyledHTML.swift
+++ b/WordPress/Classes/Extensions/NSAttributedString+StyledHTML.swift
@@ -1,4 +1,5 @@
 import UIKit
+import WordPressUI
 
 extension NSAttributedString {
     /// Creates an `NSAttributedString` with the styles defined in `attributes` applied.
@@ -43,9 +44,7 @@ extension NSAttributedString {
         paragraphStyle.paragraphSpacing = 0
         paragraphStyle.paragraphSpacingBefore = 0
 
-        attributedString.addAttribute(.paragraphStyle,
-                                      value: paragraphStyle,
-                                      range: NSMakeRange(0, attributedString.string.count - 1))
+        attributedString.applyAttribute(.paragraphStyle, value: paragraphStyle)
 
         return NSAttributedString(attributedString: attributedString)
     }
diff --git a/WordPress/Classes/Jetpack/NUX/LandingScreen/Views/JetpackLandingScreenView.swift b/WordPress/Classes/Jetpack/NUX/LandingScreen/Views/JetpackLandingScreenView.swift
index 14636f661729..9670a45e8c8e 100644
--- a/WordPress/Classes/Jetpack/NUX/LandingScreen/Views/JetpackLandingScreenView.swift
+++ b/WordPress/Classes/Jetpack/NUX/LandingScreen/Views/JetpackLandingScreenView.swift
@@ -1,4 +1,5 @@
 import UIKit
+import WordPressUI
 
 final class JetpackLandingScreenView: UIView {
 
@@ -72,7 +73,7 @@ final class JetpackLandingScreenView: UIView {
             return nil
         }
         let attributedString = NSMutableAttributedString(string: text)
-        attributedString.addAttributes(attributesForLabel(atIndex: index, traits: traits), range: NSMakeRange(0, text.utf16.count))
+        attributedString.applyAttributes(attributesForLabel(atIndex: index, traits: traits))
         return attributedString
     }
 
diff --git a/WordPress/Classes/Models/Revisions/DiffAbstractValue+Attributes.swift b/WordPress/Classes/Models/Revisions/DiffAbstractValue+Attributes.swift
index 4f426e60dbbd..01e2b5e24ea9 100644
--- a/WordPress/Classes/Models/Revisions/DiffAbstractValue+Attributes.swift
+++ b/WordPress/Classes/Models/Revisions/DiffAbstractValue+Attributes.swift
@@ -39,7 +39,7 @@ extension Array where Element == DiffAbstractValue {
 
         let attribute = NSMutableAttributedString(string: value)
         if let attributes = right.attributes {
-            attribute.addAttributes(attributes, range: NSRange(location: 0, length: value.count))
+            attribute.applyAttributes(attributes)
         }
         left.append(attribute)
         return left
diff --git a/WordPress/Classes/Utility/Blogging Reminders/BloggingRemindersScheduleFormatter.swift b/WordPress/Classes/Utility/Blogging Reminders/BloggingRemindersScheduleFormatter.swift
index 5de223f97fcd..2ce115aba51c 100644
--- a/WordPress/Classes/Utility/Blogging Reminders/BloggingRemindersScheduleFormatter.swift	
+++ b/WordPress/Classes/Utility/Blogging Reminders/BloggingRemindersScheduleFormatter.swift	
@@ -189,6 +189,6 @@ private extension String {
         guard let expression = try? NSRegularExpression(pattern: "</?strong>", options: .caseInsensitive) else {
             return self
         }
-        return expression.stringByReplacingMatches(in: self, range: NSMakeRange(0, self.count), withTemplate: String())
+        return expression.stringByReplacingMatches(in: self, range: NSMakeRange(0, self.utf16.count), withTemplate: String())
     }
 }
diff --git a/WordPress/Classes/ViewRelated/Blog/BloggingReminders/BloggingRemindersFlowCompletionViewController.swift b/WordPress/Classes/ViewRelated/Blog/BloggingReminders/BloggingRemindersFlowCompletionViewController.swift
index 09b7081e7ff8..c87473451134 100644
--- a/WordPress/Classes/ViewRelated/Blog/BloggingReminders/BloggingRemindersFlowCompletionViewController.swift
+++ b/WordPress/Classes/ViewRelated/Blog/BloggingReminders/BloggingRemindersFlowCompletionViewController.swift
@@ -177,7 +177,7 @@ final class BloggingRemindersFlowCompletionViewController: UIViewController {
 
         let promptText = NSMutableAttributedString(attributedString: formatter.longScheduleDescription(for: schedule, time: scheduler.scheduledTime(for: blog).toLocalTime()))
 
-        promptText.addAttributes(defaultAttributes, range: NSRange(location: 0, length: promptText.length))
+        promptText.applyAttributes(defaultAttributes)
         promptLabel.attributedText = promptText
     }
 
diff --git a/WordPress/Classes/ViewRelated/Blog/BloggingReminders/BloggingRemindersFlowSettingsViewController.swift b/WordPress/Classes/ViewRelated/Blog/BloggingReminders/BloggingRemindersFlowSettingsViewController.swift
index 61d8c31763b3..1f21d679a469 100644
--- a/WordPress/Classes/ViewRelated/Blog/BloggingReminders/BloggingRemindersFlowSettingsViewController.swift
+++ b/WordPress/Classes/ViewRelated/Blog/BloggingReminders/BloggingRemindersFlowSettingsViewController.swift
@@ -490,7 +490,7 @@ private extension BloggingRemindersFlowSettingsViewController {
 
         let frequencyDescription = scheduleFormatter.shortScheduleDescription(for: .weekdays(weekdays))
         let attributedText = NSMutableAttributedString(attributedString: frequencyDescription)
-        attributedText.addAttributes(defaultAttributes, range: NSRange(location: 0, length: attributedText.length))
+        attributedText.applyAttributes(defaultAttributes)
 
         frequencyLabel.attributedText = attributedText
         frequencyLabel.sizeToFit()
diff --git a/WordPress/Classes/ViewRelated/Blog/Site Management/DestructiveAlertHelper.swift b/WordPress/Classes/ViewRelated/Blog/Site Management/DestructiveAlertHelper.swift
index f5d34c42e9dc..0872b6fffcd9 100644
--- a/WordPress/Classes/ViewRelated/Blog/Site Management/DestructiveAlertHelper.swift	
+++ b/WordPress/Classes/ViewRelated/Blog/Site Management/DestructiveAlertHelper.swift	
@@ -1,4 +1,5 @@
 import UIKit
+import WordPressUI
 
 protocol DestructiveAlertHelperLogic {
     var valueToConfirm: String? { get }
@@ -18,7 +19,7 @@ class DestructiveAlertHelper: DestructiveAlertHelperLogic {
         let attributedValue: NSMutableAttributedString = NSMutableAttributedString(string: valueToConfirm)
         let paragraphStyle = NSMutableParagraphStyle()
         paragraphStyle.lineBreakMode = .byCharWrapping
-        attributedValue.addAttribute(.paragraphStyle, value: paragraphStyle, range: NSMakeRange(0, attributedValue.string.count - 1))
+        attributedValue.applyAttribute(.paragraphStyle, value: paragraphStyle)
         attributedMessage.append(attributedValue)
 
         let alert = UIAlertController(title: title, message: nil, preferredStyle: .alert)
diff --git a/WordPress/Classes/ViewRelated/Blog/Site Monitoring/SiteMonitoringEntryDetailsView.swift b/WordPress/Classes/ViewRelated/Blog/Site Monitoring/SiteMonitoringEntryDetailsView.swift
index cf5cb91ca3dc..64cb3c81e5ae 100644
--- a/WordPress/Classes/ViewRelated/Blog/Site Monitoring/SiteMonitoringEntryDetailsView.swift	
+++ b/WordPress/Classes/ViewRelated/Blog/Site Monitoring/SiteMonitoringEntryDetailsView.swift	
@@ -1,6 +1,7 @@
 import SwiftUI
 import WordPressData
 import WordPressKit
+import WordPressUI
 
 struct SiteMonitoringEntryDetailsView: View {
     let text: NSAttributedString
@@ -77,12 +78,12 @@ private func makeAttributedText(metadata: [(String, String?)], message: String?
     if let message {
         output.append(NSAttributedString(string: "\n" + message, attributes: [.font: regular]))
     }
-    output.addAttribute(.paragraphStyle, value: {
+    output.applyAttribute(.paragraphStyle, value: {
         let style = NSMutableParagraphStyle()
         style.lineSpacing = 3
         return style
-    }(), range: NSRange(location: 0, length: output.length))
-    output.addAttribute(.foregroundColor, value: UIColor.label, range: NSRange(location: 0, length: output.length))
+    }())
+    output.applyAttribute(.foregroundColor, value: UIColor.label)
     return output
 }
 
diff --git a/WordPress/Classes/ViewRelated/Comments/Controllers/CommentDetailViewController.swift b/WordPress/Classes/ViewRelated/Comments/Controllers/CommentDetailViewController.swift
index 07748d35943c..ffc500bdab25 100644
--- a/WordPress/Classes/ViewRelated/Comments/Controllers/CommentDetailViewController.swift
+++ b/WordPress/Classes/ViewRelated/Comments/Controllers/CommentDetailViewController.swift
@@ -84,7 +84,7 @@ public class CommentDetailViewController: UIViewController, NoResultsViewHost {
         let attributedString = NSMutableAttributedString()
         attributedString.append(NSAttributedString(attachment: iconAttachment))
         attributedString.append(.init(string: " " + .replyIndicatorLabelText))
-        attributedString.addAttributes(Style.ReplyIndicator.textAttributes, range: NSMakeRange(0, attributedString.length))
+        attributedString.applyAttributes(Style.ReplyIndicator.textAttributes)
 
         // reverse the attributed strings in RTL direction.
         if view.effectiveUserInterfaceLayoutDirection == .rightToLeft {
diff --git a/WordPress/Classes/ViewRelated/Jetpack/Branding/Fullscreen Overlay/JetpackFullscreenOverlayViewController.swift b/WordPress/Classes/ViewRelated/Jetpack/Branding/Fullscreen Overlay/JetpackFullscreenOverlayViewController.swift
index 449cbf2e03f8..2f35fd9de6ac 100644
--- a/WordPress/Classes/ViewRelated/Jetpack/Branding/Fullscreen Overlay/JetpackFullscreenOverlayViewController.swift	
+++ b/WordPress/Classes/ViewRelated/Jetpack/Branding/Fullscreen Overlay/JetpackFullscreenOverlayViewController.swift	
@@ -147,7 +147,7 @@ class JetpackFullscreenOverlayViewController: UIViewController {
             .kern: Metrics.titleKern
         ]
         let attributedString = NSMutableAttributedString(string: viewModel.title)
-        attributedString.addAttributes(defaultAttributes, range: NSRange(location: 0, length: attributedString.length))
+        attributedString.applyAttributes(defaultAttributes)
         titleLabel.attributedText = attributedString
     }
 
diff --git a/WordPress/Classes/ViewRelated/Jetpack/Jetpack Scan/View Models/JetpackScanThreatViewModel.swift b/WordPress/Classes/ViewRelated/Jetpack/Jetpack Scan/View Models/JetpackScanThreatViewModel.swift
index 77d087e17874..ed5d8de41a72 100644
--- a/WordPress/Classes/ViewRelated/Jetpack/Jetpack Scan/View Models/JetpackScanThreatViewModel.swift	
+++ b/WordPress/Classes/ViewRelated/Jetpack/Jetpack Scan/View Models/JetpackScanThreatViewModel.swift	
@@ -409,7 +409,7 @@ struct JetpackScanThreatViewModel {
     }
 }
 
-private extension JetpackThreatContext {
+extension JetpackThreatContext {
 
     struct JetpackThreatContextRendererConfig {
         let numberAttributes: [NSAttributedString.Key: Any]
@@ -461,26 +461,22 @@ private extension JetpackThreatContext {
 
             if let highlights = line.highlights {
 
-                numberAttr.setAttributes(config.highlightedNumberAttributes,
-                                         range: NSRange(location: 0, length: numberStr.count))
+                numberAttr.applyAttributes(config.highlightedNumberAttributes)
 
-                contentsAttr.addAttributes(config.highlightedContentsAttributes,
-                                           range: NSRange(location: 0, length: contentsStr.count))
+                contentsAttr.applyAttributes(config.highlightedContentsAttributes)
 
                 for highlight in highlights {
                     let location = highlight.location
-                    let length = highlight.length + Constants.columnSpacer.count
+                    let length = highlight.length + Constants.columnSpacer.utf16.count
                     let range = NSRange(location: location, length: length)
 
                     contentsAttr.addAttributes(config.highlightedSectionAttributes, range: range)
                 }
 
             } else {
-                numberAttr.setAttributes(config.numberAttributes,
-                                         range: NSRange(location: 0, length: numberStr.count))
+                numberAttr.applyAttributes(config.numberAttributes)
 
-                contentsAttr.setAttributes(config.contentsAttributes,
-                                           range: NSRange(location: 0, length: contentsStr.count))
+                contentsAttr.applyAttributes(config.contentsAttributes)
             }
 
             attrString.append(numberAttr)
diff --git a/WordPress/Classes/ViewRelated/Notifications/FormattableContent/Groups/BodyContentGroup.swift b/WordPress/Classes/ViewRelated/Notifications/FormattableContent/Groups/BodyContentGroup.swift
index adced12f1874..8985dfe80ac9 100644
--- a/WordPress/Classes/ViewRelated/Notifications/FormattableContent/Groups/BodyContentGroup.swift
+++ b/WordPress/Classes/ViewRelated/Notifications/FormattableContent/Groups/BodyContentGroup.swift
@@ -85,9 +85,9 @@ class BodyContentGroup: FormattableContentGroup {
         }
     }
 
-    private class func pingbackReadMoreGroup(for url: URL) -> FormattableContentGroup {
+    static func pingbackReadMoreGroup(for url: URL) -> FormattableContentGroup {
         let text = NSLocalizedString("Read the source post", comment: "Displayed at the footer of a Pingback Notification.")
-        let textRange = NSRange(location: 0, length: text.count)
+        let textRange = NSRange(location: 0, length: text.utf16.count)
         let zeroRange = NSRange(location: 0, length: 0)
 
         var properties = NotificationContentRange.Properties(range: textRange)
diff --git a/WordPress/Classes/ViewRelated/Post/Views/PostListItemViewModel.swift b/WordPress/Classes/ViewRelated/Post/Views/PostListItemViewModel.swift
index d7e8a1cbd287..597c3aa0918b 100644
--- a/WordPress/Classes/ViewRelated/Post/Views/PostListItemViewModel.swift
+++ b/WordPress/Classes/ViewRelated/Post/Views/PostListItemViewModel.swift
@@ -1,6 +1,7 @@
 import Foundation
 import WordPressData
 import WordPressShared
+import WordPressUI
 
 final class PostListItemViewModel {
     let post: Post
@@ -76,7 +77,7 @@ private func makeTitleString(for post: Post, isDisabled: Bool) -> NSAttributedSt
     paragraphStyle.lineBreakMode = .byTruncatingTail
 
     let string = NSMutableAttributedString(string: title, attributes: attributes)
-    string.addAttribute(.paragraphStyle, value: paragraphStyle, range: NSRange(location: 0, length: string.length))
+    string.applyAttribute(.paragraphStyle, value: paragraphStyle)
 
     return string
 }
@@ -95,7 +96,7 @@ private func makeExcerptString(for post: Post, isDisabled: Bool) -> NSAttributed
     paragraphStyle.lineBreakMode = .byTruncatingTail
 
     let string = NSMutableAttributedString(string: excerpt, attributes: attributes)
-    string.addAttribute(.paragraphStyle, value: paragraphStyle, range: NSRange(location: 0, length: string.length))
+    string.applyAttribute(.paragraphStyle, value: paragraphStyle)
 
     return string
 }
diff --git a/WordPress/Classes/ViewRelated/Reader/Controllers/ReaderStreamViewController+Helper.swift b/WordPress/Classes/ViewRelated/Reader/Controllers/ReaderStreamViewController+Helper.swift
index 40c90db83388..a644b0288c5f 100644
--- a/WordPress/Classes/ViewRelated/Reader/Controllers/ReaderStreamViewController+Helper.swift
+++ b/WordPress/Classes/ViewRelated/Reader/Controllers/ReaderStreamViewController+Helper.swift
@@ -185,7 +185,7 @@ extension ReaderStreamViewController {
         ])
         let icon = UIImage.gridicon(.bookmarkOutline, size: CGSize(width: 18, height: 18))
         string.replace("[bookmark-outline]", with: icon)
-        string.addAttribute(.foregroundColor, value: UIColor.secondaryLabel, range: NSRange(location: 0, length: string.length))
+        string.applyAttribute(.foregroundColor, value: UIColor.secondaryLabel)
         return string
     }
 }
diff --git a/WordPress/Classes/ViewRelated/Reader/Detail/Views/ReaderReadMoreView.swift b/WordPress/Classes/ViewRelated/Reader/Detail/Views/ReaderReadMoreView.swift
index 7b461532c119..7b9aad1a9be8 100644
--- a/WordPress/Classes/ViewRelated/Reader/Detail/Views/ReaderReadMoreView.swift
+++ b/WordPress/Classes/ViewRelated/Reader/Detail/Views/ReaderReadMoreView.swift
@@ -1,6 +1,7 @@
 import UIKit
 import SafariServices
 import WordPressData
+import WordPressUI
 
 // […]
 final class ReaderReadMoreView: UIView, UIAdaptivePresentationControllerDelegate, UIPopoverPresentationControllerDelegate {
@@ -25,7 +26,7 @@ final class ReaderReadMoreView: UIView, UIAdaptivePresentationControllerDelegate
             .font: UIFont.preferredFont(forTextStyle: .body)
         ])
         if let postURL = post.permaLink.flatMap(URL.init) {
-            string.addAttribute(.link, value: postURL, range: NSRange(location: 0, length: string.length))
+            string.applyAttribute(.link, value: postURL)
             self.postURL = postURL
         }
         textView.attributedText = string
diff --git a/WordPress/Classes/ViewRelated/Site Creation/Web Address/AddressTableViewCell.swift b/WordPress/Classes/ViewRelated/Site Creation/Web Address/AddressTableViewCell.swift
index cf57c0886935..6dabe49de8de 100644
--- a/WordPress/Classes/ViewRelated/Site Creation/Web Address/AddressTableViewCell.swift	
+++ b/WordPress/Classes/ViewRelated/Site Creation/Web Address/AddressTableViewCell.swift	
@@ -311,6 +311,8 @@ extension AddressTableViewCell {
         }
 
         let completeDomainName = NSMutableAttributedString(string: name, attributes: TextStyleAttributes.defaults)
+        // Domain names are ASCII-only (internationalized domains use Punycode),
+        // so .count == .utf16.count here and this is safe.
         let rangeOfCustomName = NSRange(location: 0, length: customName.count)
         completeDomainName.setAttributes(TextStyleAttributes.customName, range: rangeOfCustomName)
 
diff --git a/WordPress/Classes/ViewRelated/Stats/Insights/StatsTotalInsightsCell.swift b/WordPress/Classes/ViewRelated/Stats/Insights/StatsTotalInsightsCell.swift
index 56ff84ae323d..4880d27641a8 100644
--- a/WordPress/Classes/ViewRelated/Stats/Insights/StatsTotalInsightsCell.swift
+++ b/WordPress/Classes/ViewRelated/Stats/Insights/StatsTotalInsightsCell.swift
@@ -91,17 +91,18 @@ struct StatsTotalInsightsData: Equatable {
 
         let attributedString = NSMutableAttributedString(string: formattedString)
 
-        let textRange = NSMakeRange(0, formattedString.count)
-        attributedString.addAttribute(.font, value: UIFont.preferredFont(forTextStyle: .subheadline), range: textRange)
-        attributedString.addAttribute(.foregroundColor, value: UIColor.label, range: textRange)
+        attributedString.applyAttributes([
+            .font: UIFont.preferredFont(forTextStyle: .subheadline),
+            .foregroundColor: UIColor.label
+        ])
 
         let titlePlaceholderRange = (text as NSString).range(of: "%1$@")
-        let titleRange = NSMakeRange(titlePlaceholderRange.location, title.count)
+        let titleRange = NSMakeRange(titlePlaceholderRange.location, title.utf16.count)
         attributedString.addAttribute(.foregroundColor, value: UIAppColor.primary, range: titleRange)
 
         let formattedTitleString = String.localizedStringWithFormat(text, title, "%2$@")
         let countPlaceholderRange = (formattedTitleString as NSString).range(of: "%2$@")
-        let countRange = NSMakeRange(countPlaceholderRange.location, countString.count)
+        let countRange = NSMakeRange(countPlaceholderRange.location, countString.utf16.count)
         attributedString.addAttribute(.font, value: UIFont.preferredFont(forTextStyle: .subheadline).bold(), range: countRange)
 
         return attributedString
diff --git a/WordPress/Classes/ViewRelated/Stats/Period Stats/Overview/OverviewCell.swift b/WordPress/Classes/ViewRelated/Stats/Period Stats/Overview/OverviewCell.swift
index 8928454a9e1f..96ac9195e55d 100644
--- a/WordPress/Classes/ViewRelated/Stats/Period Stats/Overview/OverviewCell.swift	
+++ b/WordPress/Classes/ViewRelated/Stats/Period Stats/Overview/OverviewCell.swift	
@@ -38,8 +38,7 @@ struct OverviewTabData: FilterTabBarItem, Hashable {
     var attributedTitle: NSAttributedString? {
 
         let attributedTitle = NSMutableAttributedString(string: tabTitle.localizedUppercase)
-        attributedTitle.addAttributes([.font: WPStyleGuide.Stats.overviewCardFilterTitleFont],
-                                      range: NSMakeRange(0, attributedTitle.string.count))
+        attributedTitle.applyAttributes([.font: WPStyleGuide.Stats.overviewCardFilterTitleFont])
 
         let dataString: String = {
             if let tabDataStub {
@@ -49,8 +48,7 @@ struct OverviewTabData: FilterTabBarItem, Hashable {
         }()
 
         let attributedData = NSMutableAttributedString(string: dataString)
-        attributedData.addAttributes([.font: WPStyleGuide.Stats.overviewCardFilterDataFont],
-                                     range: NSMakeRange(0, attributedData.string.count))
+        attributedData.applyAttributes([.font: WPStyleGuide.Stats.overviewCardFilterDataFont])
 
         attributedTitle.append(NSAttributedString(string: "\n"))
         attributedTitle.append(attributedData)
diff --git a/WordPress/Classes/ViewRelated/System/FilterTabBar.swift b/WordPress/Classes/ViewRelated/System/FilterTabBar.swift
index c6c6d6491e1d..99a23da75f61 100644
--- a/WordPress/Classes/ViewRelated/System/FilterTabBar.swift
+++ b/WordPress/Classes/ViewRelated/System/FilterTabBar.swift
@@ -1,5 +1,6 @@
 import UIKit
 import WordPressShared
+import WordPressUI
 
 /// Filter Tab Bar is a tabbed control (much like a segmented control), but
 /// has an appearance similar to Android tabs.
@@ -344,7 +345,7 @@ public class FilterTabBar: UIControl {
         }
 
         let mutableString = NSMutableAttributedString(attributedString: attributedString)
-        mutableString.addAttributes([.foregroundColor: color], range: NSMakeRange(0, mutableString.string.count))
+        mutableString.applyAttributes([.foregroundColor: color])
 
         return mutableString
     }
diff --git a/WordPress/WordPressShareExtension/Sources/Services/ShareExtractor.swift b/WordPress/WordPressShareExtension/Sources/Services/ShareExtractor.swift
index 834375e39451..4909390d5c1c 100644
--- a/WordPress/WordPressShareExtension/Sources/Services/ShareExtractor.swift
+++ b/WordPress/WordPressShareExtension/Sources/Services/ShareExtractor.swift
@@ -578,7 +578,7 @@ private struct PlainTextExtractor: TypeBasedExtensionContentExtractor {
         // the selected text — we just want to make sure shared URLs are handled).
         let types: NSTextCheckingResult.CheckingType = [.link]
         let detector = try? NSDataDetector(types: types.rawValue)
-        if let match = detector?.firstMatch(in: payload, options: [], range: NSMakeRange(0, payload.count)),
+        if let match = detector?.firstMatch(in: payload, options: [], range: NSMakeRange(0, payload.utf16.count)),
             match.resultType == .link,
             let url = match.url,
             url.absoluteString.count == payload.count {