Add qt.workarounds.disable_accessibility setting

This disables accessibility with Qt 6.10.1, which
causes frequent segfaults.

Closes #8797

doc/changelog.asciidoc

@@ -15,6 +15,18 @@ breaking changes (such as renamed commands) can happen in minor releases.
 // `Fixed` for any bug fixes.
 // `Security` to invite users to upgrade in case of vulnerabilities.
 
+[[v3.6.3]]
+v3.6.3 (unreleased)
+-------------------
+
+Fixed
+~~~~~
+
+- New `qt.workarounds.disable_accessibility` setting, which disables Chromium
+  accessibility support. By default, is it set to `auto`, which only disables
+  accessibility on Qt versions with known issues. This works around a bug in Qt
+  6.10.1 causing frequent segfaults (#8797).
+
 [[v3.6.2]]
 v3.6.2 (2025-11-27)
 -------------------

doc/help/settings.asciidoc

@@ -302,6 +302,7 @@
 |<<qt.force_software_rendering,qt.force_software_rendering>>|Force software rendering for QtWebEngine.
 |<<qt.highdpi,qt.highdpi>>|Turn on Qt HighDPI scaling.
 |<<qt.workarounds.disable_accelerated_2d_canvas,qt.workarounds.disable_accelerated_2d_canvas>>|Disable accelerated 2d canvas to avoid graphical glitches.
+|<<qt.workarounds.disable_accessibility,qt.workarounds.disable_accessibility>>|Disable accessibility to avoid crashes on Qt 6.10.1.
 |<<qt.workarounds.disable_hangouts_extension,qt.workarounds.disable_hangouts_extension>>|Disable the Hangouts extension.
 |<<qt.workarounds.locale,qt.workarounds.locale>>|Work around locale parsing issues in QtWebEngine 5.15.3.
 |<<qt.workarounds.remove_service_workers,qt.workarounds.remove_service_workers>>|Delete the QtWebEngine Service Worker directory on every start.
@@ -3996,6 +3997,24 @@ Valid values:
 
 Default: +pass:[auto]+
 
+[[qt.workarounds.disable_accessibility]]
+=== qt.workarounds.disable_accessibility
+Disable accessibility to avoid crashes on Qt 6.10.1.
+
+This setting requires a restart.
+
+This setting is only available with the QtWebEngine backend.
+
+Type: <<types,String>>
+
+Valid values:
+
+ * +always+: Disable renderer accessibility
+ * +auto+: Disable on Qt versions with known issues, enable otherwise
+ * +never+: Enable renderer accessibility
+
+Default: +pass:[auto]+
+
 [[qt.workarounds.disable_hangouts_extension]]
 === qt.workarounds.disable_hangouts_extension
 Disable the Hangouts extension.

qutebrowser/config/configdata.yml

@@ -422,6 +422,19 @@ qt.workarounds.disable_hangouts_extension:
     disabled to avoid crashes on Qt 6.5.0 to 6.5.3 if dark mode is enabled,
     as well as on Qt 6.6.0.
 
+qt.workarounds.disable_accessibility:
+  type:
+    name: String
+    valid_values:
+      - always: Disable renderer accessibility
+      - auto: Disable on Qt versions with known issues, enable otherwise
+      - never: Enable renderer accessibility
+  default: auto
+  backend: QtWebEngine
+  restart: true
+  desc: >-
+    Disable accessibility to avoid crashes on Qt 6.10.1.
+
 ## auto_save
 
 auto_save.interval:

qutebrowser/config/qtargs.py

@@ -362,6 +362,16 @@ _WEBENGINE_SETTINGS: dict[str, dict[Any, Optional[_SettingValueType]]] = {
         and versions.webengine < utils.VersionNumber(6, 8, 2)
         else None,
     },
+    'qt.workarounds.disable_accessibility': {
+        'always': '--disable-renderer-accessibility',
+        'never': None,
+        # WORKAROUND for https://qt-project.atlassian.net/browse/QTBUG-142320
+        'auto': lambda versions: '--disable-renderer-accessibility'
+        if machinery.IS_QT6
+        and versions.webengine
+        and versions.webengine == utils.VersionNumber(6, 10, 1)
+        else None,
+    },
 }
 
 

tests/unit/config/test_qtargs.py

@@ -12,7 +12,7 @@ import pytest
 from qutebrowser.qt import machinery
 from qutebrowser import qutebrowser
 from qutebrowser.config import qtargs, configdata
-from qutebrowser.utils import usertypes, version
+from qutebrowser.utils import usertypes, version, utils
 
 
 @pytest.fixture
@@ -52,6 +52,7 @@ def reduce_args(config_stub, version_patcher, monkeypatch):
     config_stub.val.scrolling.bar = 'never'
     config_stub.val.qt.chromium.experimental_web_platform_features = 'never'
     config_stub.val.qt.workarounds.disable_accelerated_2d_canvas = 'never'
+    config_stub.val.qt.workarounds.disable_accessibility = 'never'
     monkeypatch.setattr(qtargs.utils, 'is_mac', False)
     # Avoid WebRTC pipewire feature
     monkeypatch.setattr(qtargs.utils, 'is_linux', False)
@@ -117,6 +118,14 @@ def test_no_webengine_available(monkeypatch, config_stub, parser, stubs):
     assert args == [sys.argv[0]]
 
 
+_XFAIL_FUTURE_QT = (
+    pytest.mark.xfail(
+        utils.VersionNumber(6, 11) not in version.WebEngineVersions._CHROMIUM_VERSIONS,
+        reason="Unknown security patch version for Qt 6.11 so far",
+    ),
+)
+
+
 @pytest.mark.usefixtures('reduce_args')
 class TestWebEngineArgs:
 
@@ -190,6 +199,40 @@ class TestWebEngineArgs:
         args = qtargs.qt_args(parsed)
         assert ('--disable-accelerated-2d-canvas' in args) == has_arg
 
+    @pytest.mark.parametrize(
+        "qt_version, qt6, value, has_arg",
+        [
+            ("5.15.2", False, "auto", False),
+            # 6.8.5 is broken too, but commercial-only
+            ("6.10.0", True, "always", True),
+            ("6.10.0", True, "auto", False),
+            ("6.10.1", True, "auto", True),
+            ("6.10.1", True, "never", False),
+            ("6.10.2", True, "always", True),
+            ("6.10.2", True, "auto", False),
+            pytest.param("6.11.0", True, "always", True, marks=_XFAIL_FUTURE_QT),
+            pytest.param("6.11.0", True, "auto", False, marks=_XFAIL_FUTURE_QT),
+        ],
+    )
+    def test_disable_accessibility(
+        self,
+        parser,
+        version_patcher,
+        config_stub,
+        monkeypatch,
+        qt_version,
+        qt6,
+        value,
+        has_arg,
+    ):
+        version_patcher(qt_version)
+        config_stub.val.qt.workarounds.disable_accessibility = value
+        monkeypatch.setattr(machinery, 'IS_QT6', qt6)
+
+        parsed = parser.parse_args([])
+        args = qtargs.qt_args(parsed)
+        assert ('--disable-renderer-accessibility' in args) == has_arg
+
     @pytest.mark.parametrize('flags, args', [
         ([], []),
         (['--debug-flag', 'chromium'], ['--enable-logging', '--v=1']),