STR: 1. Hover over "Open a new tab" button in tab bar and see that it need some tuning to be like on Photon specification - http://design.firefox.com/people/shorlander/photon/Mockups/windows-7.html Some data "Open a new tab" button size: 36 x 26 px - before landing patch from bug #1377184 28 x 28 px - after landing patch from bug #1377184 28 x 28 px - in Photon specification "Open a new tab" button active hover area: 36 x 26 px - before landing patch from bug #1377184 36 x 26 px - after landing patch from bug #1377184 28 x 28 px - in Photon specification Space between Tab and "Open a new tab" button: 4 px - after landing patch from bug #1377184 2 px - in Photon specification So in tl;dr "Open a new tab" button: - should be moved 2 px to the left - active hover area should be only on the button area Regression range pushlog: https://hg.mozilla.org/integration/autoland/json-pushes?changeset=500a01cf896dbb9883cb85f162552e20b8facfc0&full=1 Caused by: Bug 1377184 - Use new Photon hover effect also on "Show more bookmarks" and extensions buttons icons in Bookmarks Toolbar

One more thing. Looks like the "Open a new tab" button has slightly different parameters for every UI density option. For example there is only 1 px gap between Tab and Open a new tab button in Compact mode.

I forgot to mention, that my screenshots are with Compact density mode.

As far as I can see all your screenshots are from Normal density mode. Check the density options on the Mockup page. There is a difference in Back button design.

Ops, yes, you're right.

(In reply to Virtual_ManPL [:Virtual] - (please needinfo? me - so I will see your comment/reply/question/etc.) from comment #0) > So in tl;dr "Open a new tab" button: > - should be moved 2 px to the left > - active hover area should be only on the button area We don't have plans to do the latter. Morphing bug.

Comment on attachment 8898661 [details] Bug 1389921 - Stop setting a width on the new tab button to remove excess padding around it. https://reviewboard.mozilla.org/r/170042/#review175932 Looks good cheers

Pushed by dgottwald@mozilla.com: https://hg.mozilla.org/integration/autoland/rev/cc018eee995b Stop setting a width on the new tab button to remove excess padding around it. r=daleharvey

Just for the record, this caused some conflicts when I merged bug 1352119 to m-c from inbound. I think I resolved it correctly, though.

(In reply to Wes Kocher (:KWierso) from comment #17) > Just for the record, this caused some conflicts when I merged bug 1352119 to > m-c from inbound. I think I resolved it correctly, though. Looks like it.

I'm confirming that bug is fixed, starting in Mozilla Firefox Nightly 57.0a1 (2017-08-22), so I'm marking this bug as VERIFIED. Thanks.

Screenshots: https://screenshots.mattn.ca/compare/?oldProject=mozilla-central&oldRev=a9d372645a32b8d23d44244f351639af9d73b96a&newProject=mozilla-central&newRev=c7570eb46382ee56d081e549b484341f400c864b