Hi developers, I request that bundled or "vendored" sources copied from other upstream projects should live under a directory named "ThirdParty" so we can keep track of it. Not knowing about bundled sources causes various problems, e.g. we've previously shipped unused libavif and dav1d sources in WebCore due to not knowing about them. Ideally third-party code should be placed in Source/ThirdParty. If the requirements of Apple's internal build system do not allow for putting the code in Source/ThirdParty, then you can create a new ThirdParty directory wherever needed, e.g. Source/WebCore/PAL/ThirdParty. Currently we have at least wtf/simde and wtf/simdutf violating these guidelines. If somebody with XCode could please create a wtf/ThirdParty and move the directories to there, that would be helpful. Unfortunately it's not easy to move sources without XCode. If you know of other bundled sources elsewhere in WebKit, let's do the similar moves for those as well. (This rule doesn't need to apply for minimal one-time copying, like taking just a useful file or two from an upstream project and incorporating it into WebKit. Of course that is fine. We just shouldn't have entire upstream projects hidden in WebKit.) Thanks, Michael