I have a testcase that has a <div> with an outline, containing an <img> which has a CSS mask set to an SVG file. For some reason, the mask contains the outline too.
Created attachment 30694 [details] Screenshot
Created attachment 30695 [details] SVG circle for testcase
Created attachment 30696 [details] Testcase
To see the problem with the attached testcase, you need to resize the window after the SVG loads.
This might have been an problem with subpixel layout of SVG. I can reproduce it on Safari or Chromium. Can we close the bug?
I don't know what might have fixed this, but it doesn't seem to reproduce any more.