Rules like: ::-internal-blah {} are parsed as valid CSS, but the SelectorChecker will never match. They should be dropped at parse time.
Unfortunately, some of them do match. Just make sure you are not removing those.
It's only ::-internal-media-controls-overlay-cast-button, afaict.
https://chromium-review.googlesource.com/c/512827/
The following revision refers to this bug: https://chromium.googlesource.com/chromium/src.git/+/ff8ac992b2d0476ee7806728fcbf003600807efd commit ff8ac992b2d0476ee7806728fcbf003600807efd Author: Rune Lillesveen <rune@opera.com> Date: Fri May 26 12:42:34 2017 Drop author ::-internal-* pseudo at parse time. The SelectorChecker already always failed, but the selector should be invalid and the whole rule dropped. There is a single pseudo ::-internal-media-controls-overlay-cast-button which is still web- facing. That is tracked by issue 678285. Moved the update pseudo page in @page into a separate method. BUG= 725480 ,678285 Change-Id: Ifca8a0e593c4d11720b0b0822e4c753ff45fb52b Reviewed-on: https://chromium-review.googlesource.com/512827 Commit-Queue: Rune Lillesveen <rune@opera.com> Reviewed-by: Mounir Lamouri <mlamouri@chromium.org> Cr-Commit-Position: refs/heads/master@{#474987} [modify] https://crrev.com/ff8ac992b2d0476ee7806728fcbf003600807efd/third_party/WebKit/LayoutTests/FlagExpectations/enable-blink-features=LayoutNG [delete] https://crrev.com/3e04e43e54065fb3b758200e23efb25697ead7e9/third_party/WebKit/LayoutTests/fast/css/invalidation/spatial-navigation-focus-pseudo-expected.txt [delete] https://crrev.com/3e04e43e54065fb3b758200e23efb25697ead7e9/third_party/WebKit/LayoutTests/fast/css/invalidation/spatial-navigation-focus-pseudo.html [modify] https://crrev.com/ff8ac992b2d0476ee7806728fcbf003600807efd/third_party/WebKit/LayoutTests/media/deprecated-css-selectors.html [modify] https://crrev.com/ff8ac992b2d0476ee7806728fcbf003600807efd/third_party/WebKit/Source/core/css/CSSSelector.cpp [modify] https://crrev.com/ff8ac992b2d0476ee7806728fcbf003600807efd/third_party/WebKit/Source/core/css/CSSSelector.h [modify] https://crrev.com/ff8ac992b2d0476ee7806728fcbf003600807efd/third_party/WebKit/Source/core/css/SelectorChecker.cpp [modify] https://crrev.com/ff8ac992b2d0476ee7806728fcbf003600807efd/third_party/WebKit/Source/core/css/parser/CSSParserImpl.cpp [modify] https://crrev.com/ff8ac992b2d0476ee7806728fcbf003600807efd/third_party/WebKit/Source/core/css/parser/CSSParserSelector.h [modify] https://crrev.com/ff8ac992b2d0476ee7806728fcbf003600807efd/third_party/WebKit/Source/core/css/parser/CSSSelectorParser.cpp [modify] https://crrev.com/ff8ac992b2d0476ee7806728fcbf003600807efd/third_party/WebKit/Source/core/css/parser/CSSSelectorParserTest.cpp [modify] https://crrev.com/ff8ac992b2d0476ee7806728fcbf003600807efd/third_party/WebKit/Source/core/html/HTMLVideoElementPersistentTest.cpp
Comment 1 by phistuck@gmail.com
, May 23 2017