Test cases showing flaws in various browsers. Errors are described in the test files.
macOS 11.6.1, Chrome Canary 98.0.4713.0 - DevTools Network Tab Layout Broken (screenshot)
Android 7.0.0, Chrome 64.0.3282.137 - Multiple Backgrounds (screenshot)
Android 7.0.0, Chrome 64.0.3282.137 - Filtered Background (screenshot)