(In reply to Andrew Halberstadt [:ahal] from comment #4)
On Linux, mochitest-browser-chrome was previously not running with webrender enabled at all, so it's not too surprising that there are more problems there. Maybe we should leave fission as non-webrender on Linux for now and work on enabling regular browser-chrome with webrender as a prerequisite..
That's a bummer. I'll follow up with the WebRender team about the failures.
In the meantime, let's follow your suggestion and leave Fission as non-WebRender for mochitest-browser-chrome on Linux. We'll probably have fewer problems, even though Fission without WebRender is not an officially-supported configuration.
I'll see if I can disable tests to victory on Mac and Windows.
If you will have to disable a lot of tests on Mac and Windows, feel free to instead try running mochitest-browser-chrome without WebRender there, too. Testing Fission, not WebRender, is the priority. :)
Edit: I see now that we already run mochitest-browser-chrome with WebRender for e10s on Mac and Windows, so any test problems with mochitest-browser-chrome for Fission+WebRender will be Fission's fault.