In bug 1384686 I introduced --toolbarbutton-icon-fill-opacity but accidentally didn't use it for the scroll buttons.

Comment on attachment 8910685 [details] Bug 1401917 - Let tab strip scroll buttons use --toolbarbutton-icon-fill-opacity. https://reviewboard.mozilla.org/r/182142/#review187512

Pushed by dgottwald@mozilla.com: https://hg.mozilla.org/integration/autoland/rev/32d758581c46 Let tab strip scroll buttons use --toolbarbutton-icon-fill-opacity. r=nhnt11

Comment on attachment 8910685 [details] Bug 1401917 - Let tab strip scroll buttons use --toolbarbutton-icon-fill-opacity. Approval Request Comment [Feature/Bug causing the regression]: photon-visual polish [User impact if declined]: inconsistent icon opacity [Is this code covered by automated tests?]: no [Has the fix been verified in Nightly?]: not yet [Needs manual test from QE? If yes, steps to reproduce]: let the tab strip overflow and compare that the scroll buttons's opacity to that of other icons [List of other uplifts needed for the feature/fix]: / [Is the change risky?]: no [Why is the change risky/not risky?]: trivial isolated fix [String changes made/needed]: /

Comment on attachment 8910685 [details] Bug 1401917 - Let tab strip scroll buttons use --toolbarbutton-icon-fill-opacity. Polish photon, taking it. Should be in 57b3

Tested on Nightly 58.0a1 Build ID 20170924220116 Mozilla/5.0 (Macintosh; Intel Mac OS X 10.12; rv:58.0) Gecko/20100101 Firefox/58.0 Inconsistency for scroll buttons's opacity is fixed. I will mark this as Verified Fixed. Thank you

Let's make sure this works as expected on Beta 57 as well.

The inconsistency for scroll button's opacity on Firefox 57.0b9 is now fixed. Marked accordingly.