[htmlhelp] do not add checksums to css files if building using the htmlhelp builder (#11894)

Co-authored-by: Jan-Hendrik Garber <jan-hendrik.garber@avanquest.com>
Co-authored-by: Adam Turner <9087854+aa-turner@users.noreply.github.com>

Author: 3 people

CHANGES.rst

@@ -96,6 +96,8 @@ Bugs fixed
 * #11278: autodoc: Fix rendering of :class:`functools.singledispatchmethod`
   combined with :func:`@classmethod <classmethod>`.
   Patch by Bénédikt Tran.
+* #11894: Do not add checksums to css files if building using the htmlhelp builder.
+  Patch by mkay.
 
 Testing
 -------

sphinx/builders/html/__init__.py

@@ -1052,7 +1052,9 @@ def css_tag(css: _CascadingStyleSheet) -> str:
                      if value is not None]
             uri = pathto(os.fspath(css.filename), resource=True)
             # the EPUB format does not allow the use of query components
-            if self.name != 'epub':
+            # the Windows help compiler requires that css links
+            # don't have a query component
+            if self.name not in {'epub', 'htmlhelp'}:
                 if checksum := _file_checksum(outdir, css.filename):
                     uri += f'?v={checksum}'
             return f'<link {" ".join(sorted(attrs))} href="{uri}" />'