228828 2021-08-05 08:25:33 -0700 WebM is not enabled in WebKitTestRunner when GPU Process is used 2022-08-11 03:35:23 -0700 1 1 1 Unclassified WebKit Media WebKit Local Build Unspecified Unspecified NEW InRadar P2 Normal --- 228830 243818 1 kkinnunen webkit-unassigned jer.noble peng.liu6 webkit-bug-importer oldest_to_newest 1782211 0 kkinnunen 2021-08-05 08:25:33 -0700 WebM is not enabled in WebKitTestRunner when GPU Process is used void GPUProcessProxy::updatePreferences() { .... WebPageGroup::forEach([&] (auto& group) mutable { if (!group.preferences().useGPUProcessForMediaEnabled()) return; #if ENABLE(OPUS) if (group.preferences().opusDecoderEnabled()) hasEnabledOpus = true; #endif #if ENABLE(VORBIS) if (group.preferences().vorbisDecoderEnabled()) hasEnabledVorbis = true; #endif #if ENABLE(WEBM_FORMAT_READER) if (group.preferences().webMFormatReaderEnabled()) hasEnabledWebMFormatReader = true; #endif #if ENABLE(MEDIA_SOURCE) && ENABLE(VP9) if (group.preferences().webMParserEnabled()) hasEnabledWebMParser = true; #endif }); ... It's not correct to iterate the WebPageGroup::forEach. The WebKitTestRunner and MiniBrowser do not seem to use a preferences object that is part of a WebPageGroup. They seem to be using a brand new preferences object. Tested by: run-webkit-tests --debug --force media/media-can-play-webm.html (observe the double negative result expectations in internal) 1782215 1 kkinnunen 2021-08-05 08:27:29 -0700 One option would be to just simplify and unilaterally always enable the codecs and the format reader in the GPU process. If I understand correctly there shouldn't be any security downside, at least. 1783828 2 webkit-bug-importer 2021-08-12 08:26:18 -0700 <rdar://problem/81850175>