Maintenance: Remove sphinx-build-compatibility

Author: amotl

src/crate/theme/rtd/conf/__init__.py

@@ -209,35 +209,6 @@
 
 def setup(app):
 
-    def setup_sphinx_compatibility():
-        """
-        Resolve problem with `sphinx_build_compatibility` extension.
-
-        Add Sphinx extension at runtime, in order to be able to configure it previously.
-        This is needed because it has some quirks that reveal themselves when invoked in
-        non-RTD environments.
-
-        - https://github.com/crate/crate-docs-theme/issues/536
-        - https://about.readthedocs.com/blog/2024/07/addons-by-default/
-        - https://github.com/readthedocs/sphinx-build-compatibility
-        """
-
-        # Extension error (sphinx_build_compatibility.extension):
-        # Handler <function manipulate_config at 0x10a4289a0> for event 'config-inited' threw an exception
-        # (exception: argument of type 'NoneType' is not iterable)
-        os.environ.setdefault("READTHEDOCS_GIT_CLONE_URL", "")
-
-        # IndexError: list index out of range
-        # project_id = response_project["results"][0]["id"]
-        # Currently needs a valid project on PyPI. Long-term fix should go into upstream code.
-        os.environ.setdefault("READTHEDOCS_PROJECT", "crate-docs-theme")
-
-        # Exception: 'NoneType' object is not subscriptable
-        os.environ.setdefault("READTHEDOCS_GIT_COMMIT_HASH", "")
-
-        # Register vendorized Sphinx plugin.
-        app.setup_extension("crate.theme.vendor.rtd_compat.extension")
-
     # Configure Sphinx/RTD to host projects on a custom domain, but also on a non-root resource.
     def configure_self_hosted_on_path(app_inited):
         """