Created attachment 417504 [details] testcase Steps to reproduce: 1. open the testcase 2. click the "Set filter" button Expected result: The image becomes blurred. Actual result: The image is blurred, but also stretched a bit. (I've observed even worse distortion when more complicated filters are added.) I've tested Firefox and Chrome, and neither of them has this problem. After some diagnose, I think this is because `feComponentTransfer` doesn't work correctly when the SVG is not somehow rendered. This behavior can be easily reproduced if the SVG element is `display: none`. (Note that Firefox shows nothing when SVG element is `display: none` though, not sure whose behavior is correct here.) That makes me think that the distorted state being persisted is probably related to bug 99996 that even if the SVG element is correctly rendered, the filter result is not updated accordingly.
The stretching seems to be related to Retina scaling (but only vertically?)
<rdar://problem/73160574>
Created attachment 418428 [details] reduced test case The stretching bug can occur with just static pages, i.e. no DOM change is needed to reproduce the bug.
This is a regression of r262893.
Created attachment 418673 [details] more reduced test case
Created attachment 418688 [details] Patch
Comment on attachment 418688 [details] Patch View in context: https://bugs.webkit.org/attachment.cgi?id=418688&action=review > LayoutTests/fast/hidpi/filters-component-transfer-expected.html:7 > + filter: url("#a"); You can remove this here.
Created attachment 418699 [details] Patch
Created attachment 418700 [details] Patch
Committed r272059: <https://trac.webkit.org/changeset/272059> All reviewed patches have been landed. Closing bug and clearing flags on attachment 418700 [details].