Repro: http://jsbin.com/jaqofi/2/edit?html,output As soon as a shadow root is added to an element, its children do not have CSS transitions. In this example: span { transition: background 2s; } body.green span { background: green; } ... <button onclick="document.body.classList.toggle('green')">Transition</button> <div> <span>No shadow root</span> </div> <div class="shadow"> <span>Projected in shadow root</span> </div> ... document.querySelector('div.shadow').attachShadow({mode:'open'}).innerHTML = '<slot></slot>'; the second span does not transition.
*** This bug has been marked as a duplicate of bug 160427 ***
This is still a bug despite bug 160427 being fixed
This might be related to: https://bugs.webkit.org/show_bug.cgi?id=164577 https://bugs.webkit.org/show_bug.cgi?id=164577 https://bugs.webkit.org/show_bug.cgi?id=164608
This is still broken so maybe it's the same issue as https://bugs.webkit.org/show_bug.cgi?id=164608 ?
<rdar://problem/29231901>
Created attachment 295495 [details] patch
Comment on attachment 295495 [details] patch Attachment 295495 [details] did not pass mac-ews (mac): Output: http://webkit-queues.webkit.org/results/2584603 New failing tests: compositing/updates/no-style-change-updates.html
Created attachment 295525 [details] Archive of layout-test-results from ews101 for mac-yosemite The attached test failures were seen while running run-webkit-tests on the mac-ews. Bot: ews101 Port: mac-yosemite Platform: Mac OS X 10.10.5
Comment on attachment 295495 [details] patch Attachment 295495 [details] did not pass mac-debug-ews (mac): Output: http://webkit-queues.webkit.org/results/2584653 New failing tests: compositing/updates/no-style-change-updates.html
Created attachment 295527 [details] Archive of layout-test-results from ews114 for mac-yosemite The attached test failures were seen while running run-webkit-tests on the mac-debug-ews. Bot: ews114 Port: mac-yosemite Platform: Mac OS X 10.10.5
Comment on attachment 295495 [details] patch Attachment 295495 [details] did not pass mac-wk2-ews (mac-wk2): Output: http://webkit-queues.webkit.org/results/2584682 New failing tests: compositing/layer-creation/translate-transition-overlap.html compositing/updates/no-style-change-updates.html
Created attachment 295531 [details] Archive of layout-test-results from ews106 for mac-yosemite-wk2 The attached test failures were seen while running run-webkit-tests on the mac-wk2-ews. Bot: ews106 Port: mac-yosemite-wk2 Platform: Mac OS X 10.10.5
Comment on attachment 295495 [details] patch Attachment 295495 [details] did not pass ios-sim-ews (ios-simulator-wk2): Output: http://webkit-queues.webkit.org/results/2584751 New failing tests: compositing/updates/no-style-change-updates.html
Created attachment 295534 [details] Archive of layout-test-results from ews125 for ios-simulator-wk2 The attached test failures were seen while running run-webkit-tests on the ios-sim-ews. Bot: ews125 Port: ios-simulator-wk2 Platform: Mac OS X 10.11.6
https://trac.webkit.org/r209065 (with a fix for the failing test)
(In reply to comment #15) > https://trac.webkit.org/r209065 (with a fix for the failing test) It broke the GTK build: https://build.webkit.org/builders/GTK%20Linux%2064-bit%20Release%20%28Build%29/builds/75132
and the Apple Windows build too: https://build.webkit.org/builders/Apple%20Win%20Release%20%28Build%29/builds/82191
https://trac.webkit.org/r209066 should help