There's a bunch of setLineHeight calls in RenderTheme / StyleAdjuster that happen when all other CSS values have already been computed. So the lh units will refer to a line-height that's fundamentally wrong. I filed https://github.com/w3c/csswg-drafts/issues/3257 on that a while ago but it seems WebKit has implemented the broken behavior :(
Ah, that's a MainThreadNeverDestroyed, introduced by: https://bugs.webkit.org/show_bug.cgi?id=211264 So this is a regression from that change.
(In reply to Emilio Cobos Álvarez (:emilio) from comment #1) > Ah, that's a MainThreadNeverDestroyed, introduced by: > > https://bugs.webkit.org/show_bug.cgi?id=211264 > > So this is a regression from that change. Could you upload the crash trace of this? If non main thread is touching `const AtomString` generated by `MainThreadNeverDestroyed<>`, this potentially means that `MainThreadNeverDestroyed<>` finds the real bug.
(In reply to Yusuke Suzuki from comment #2) > (In reply to Emilio Cobos Álvarez (:emilio) from comment #1) > > Ah, that's a MainThreadNeverDestroyed, introduced by: > > > > https://bugs.webkit.org/show_bug.cgi?id=211264 > > > > So this is a regression from that change. > > Could you upload the crash trace of this? If non main thread is touching > `const AtomString` generated by `MainThreadNeverDestroyed<>`, this > potentially means that `MainThreadNeverDestroyed<>` finds the real bug. OK, found that, thanks :)
(In reply to Yusuke Suzuki from comment #3) > (In reply to Yusuke Suzuki from comment #2) > > (In reply to Emilio Cobos Álvarez (:emilio) from comment #1) > > > Ah, that's a MainThreadNeverDestroyed, introduced by: > > > > > > https://bugs.webkit.org/show_bug.cgi?id=211264 > > > > > > So this is a regression from that change. > > > > Could you upload the crash trace of this? If non main thread is touching > > `const AtomString` generated by `MainThreadNeverDestroyed<>`, this > > potentially means that `MainThreadNeverDestroyed<>` finds the real bug. > > OK, found that, thanks :) Looks like that patch (adding new assertions) found a GTK specific bug, which cannot be caught due to lack of GTK Debug EWS.
Yes, sorry, but I pasted comment 1 in the wrong bug, should've been in bug 211355, that's why I tagged it as off-topic.
(In reply to Emilio Cobos Álvarez (:emilio) from comment #5) > Yes, sorry, but I pasted comment 1 in the wrong bug, should've been in bug > 211355, that's why I tagged it as off-topic. np! Thanks for reporting :D
rdar://96305580
Given the resolution in [1], this issue is most likely a Wontfix? [1] https://github.com/w3c/csswg-drafts/issues/3257#issuecomment-1204146452