Steps to reproduce: 1. Open https://onedrive.live.com/download?cid=F96BA52A2AF70D03&resid=F96BA52A2AF70D03!1476&authkey=APfKZqnv1yfw-RE. 2. Go to the scroll box. 3. Drag the scrollbar left. Actual results: Scrollbar moves in opposite direction with horizontal scrolling. See https://www.youtube.com/watch?v=RQ7jw_3S_mY

Regression range: https://hg.mozilla.org/integration/autoland/pushloghtml?fromchange=4cbc57e29e25e8abe783b16915bd74325a040b02&tochange=d7518eef6b8924b4ddad6cdeeae4eed1c6129b26 Regressed by: bug 1324117

Pushlog with enabled apz.drag.enabled = true; https://hg.mozilla.org/integration/mozilla-inbound/pushloghtml?fromchange=bd2089fe075e09bb3cbee1535e8ae960598f65c5&tochange=b72ab182dd554343b504a771e535214de53b5d6f Regressed by: bug 1273137

[Tracking Requested - why for this release]:

I can look into this.

For posterity, attaching the test page as an attachment to the bug.

Comment on attachment 8883669 [details] Bug 1378247 - Properly handle async scrollbar-dragging of RTL scrollframes. https://reviewboard.mozilla.org/r/154576/#review159686 Thanks for looking at this!

Pushed by kgupta@mozilla.com: https://hg.mozilla.org/integration/autoland/rev/b9aed48eb292 Properly handle async scrollbar-dragging of RTL scrollframes. r=botond

Can you confirm the issue is fixed for you in today's nightly? Thanks!

I confirm this bug has been fixed in the latest nightly build.

Comment on attachment 8883669 [details] Bug 1378247 - Properly handle async scrollbar-dragging of RTL scrollframes. Approval Request Comment [Feature/Bug causing the regression]: Async scrollbar dragging [User impact if declined]: scrollbar dragging on RTL scrollframes doesn't work properly [Is this code covered by automated tests?]: no [Has the fix been verified in Nightly?]: yes [Needs manual test from QE? If yes, steps to reproduce]: no, already verified [List of other uplifts needed for the feature/fix]: none [Is the change risky?]: not really [Why is the change risky/not risky?]: small code change to remove an assumption about valid scroll positions [String changes made/needed]: none

Comment on attachment 8883669 [details] Bug 1378247 - Properly handle async scrollbar-dragging of RTL scrollframes. fix for apz with rtl, verified in nightly, beta55+

(In reply to Kartikaya Gupta (email:kats@mozilla.com) from comment #12) > [Is this code covered by automated tests?]: no > [Has the fix been verified in Nightly?]: yes > [Needs manual test from QE? If yes, steps to reproduce]: no, already verified Setting qe-verify- based on Kartikaya's assessment on manual testing needs.