inspector/css/selector-dynamic-specificity.html crashes sometimes, and it actually might have started recently (flakiness dashboard shows crashes on January 29 and today). It's also slow (probably needs a [ Slow ] expectation), but that's a separate issue. https://webkit-test-results.appspot.com/dashboards/flakiness_dashboard.html#showAllRuns=true&tests=inspector%2Fcss%2Fselector-dynamic-specificity.html Thread 0 Crashed:: Dispatch queue: com.apple.main-thread 0 com.apple.JavaScriptCore 0x000000011024260a WTFCrash + 42 (Assertions.cpp:321) 1 com.apple.WebCore 0x0000000113e4c7e1 JSC::asObject(JSC::JSCell*) + 65 (JSObject.h:1190) 2 com.apple.WebCore 0x0000000113e4c790 JSC::asObject(JSC::JSValue) + 32 (JSObject.h:1196) 3 com.apple.WebCore 0x0000000113e4cb95 JSC::Register::function() const + 85 (JSObject.h:1473) 4 com.apple.WebCore 0x0000000113e4cafc JSC::ExecState::callee() const + 28 (CallFrame.h:46) 5 com.apple.WebCore 0x0000000113f41f75 JSC::ExecState::lexicalGlobalObject() const + 21 (JSScope.h:244) 6 com.apple.WebCore 0x00000001157de565 WebCore::domWindowFromExecState(JSC::ExecState*) + 21 (ScriptState.cpp:52) 7 com.apple.WebCore 0x0000000115cfa608 WebCore::WebInjectedScriptManager::discardInjectedScriptsFor(WebCore::DOMWindow*) + 664 (WebInjectedScriptManager.cpp:76) 8 com.apple.WebCore 0x0000000115cc8613 WebCore::WebConsoleAgent::frameWindowDiscarded(WebCore::DOMWindow*) + 259 (WebConsoleAgent.cpp:68) 9 com.apple.WebCore 0x0000000114a83938 WebCore::InspectorInstrumentation::frameWindowDiscardedImpl(WebCore::InstrumentingAgents&, WebCore::DOMWindow*) + 56 (InspectorInstrumentation.cpp:191) 10 com.apple.WebCore 0x00000001143e4d58 WebCore::InspectorInstrumentation::frameWindowDiscarded(WebCore::Frame*, WebCore::DOMWindow*) + 56 (InspectorInstrumentation.h:547) 11 com.apple.WebCore 0x0000000114615ee4 WebCore::FrameLoader::clear(WebCore::Document*, bool, bool, bool) + 324 (FrameLoader.cpp:628) 12 com.apple.WebCore 0x0000000114347252 WebCore::DocumentWriter::begin(WebCore::URL const&, bool, WebCore::Document*) + 498 (DocumentWriter.cpp:142)