The Photon mockups show that the application window should have a native top border edge accent color but the current Nightly does not have one.

Can no longer reproduce in today's 2017-07-04 build. No bug was fixed for it specifically. Can anyone confirm?

Yes, no longer reproduce in today's 2017-07-04 build. per https://developer.mozilla.org/en-US/docs/Mozilla/Bugzilla/What_to_do_and_what_not_to_do_in_Bugzilla#Resolving_bugs_as_WORKSFORME

It disappeared again on today's 2017-07-11 build.

Regressed by Bug 1375743. Fixed by setting layers.mlgpu.dev-enabled = false.

Ni per comment #4 - dvander, could you take a look?

Thanks, I can reproduce this. It looks like AL is failing to force a clear of the non-client area, which the old compositor does. This should be easy to fix.

We have two different regions to clear: the area not covered by opaque pixels, and the area that must be clear after rendering is finished. This patch refactors the clear code in RenderViewMLGPU so it can be re-used for separate draw calls. The only reason this code exists to begin with is so we can use ClearView if it's available, since it's much faster. And unfortunately the inputs to ClearView are totally different versus the clear shader.

This renames the existing clear operation to a "pre-clear" and the new clear operation is a "post-clear". The post-clear region is clamped to the invalid area, and is added to the initial opaque area.

Pushed by danderson@mozilla.com: https://hg.mozilla.org/integration/mozilla-inbound/rev/59d05f6cda7a Add a helper for automating ClearView and clear-shader operations. (bug 1378095 part 1, r=mattwoodrow) https://hg.mozilla.org/integration/mozilla-inbound/rev/cec67bb0c301 Fix Advanced Layers not forcing a clear for the window theme. (bug 1378095 part 2, r=mattwoodrow)

https://hg.mozilla.org/mozilla-central/rev/59d05f6cda7a https://hg.mozilla.org/mozilla-central/rev/cec67bb0c301