1458025 - The autoscroll direction indicator is drawn drastically offset from the mouse position on Linux Nightly

Status: RESOLVED DUPLICATE of bug 1457763

(Core :: XUL, defect)

Description

[Chris Siebenmann]

Normally when you autoscroll, the autoscroll direction indicator is drawn at your starting mouse position. On Linux Nightly, it is now drawn significantly offset from this position; how much offset seems to depend on how far from the top left corner the mouse position is when you start the autoscroll. On my display (two 1920x1200 panels side by side), it can easily be far outside the Firefox window.

(By the autoscroll direction indicator I mean the grey icon that appears with directional arrows to tell you which directions you can autoscroll in by moving the mouse.)

My environment is Fedora 27, x86_64, AMD Radeon graphics, under X (not Wayland), and my displays are not HiDPI. This is a recent change but I have yet to go hunting for the specific breakage point.

Comment 1

[Sebastian Hengst [:aryx] (needinfo me if it's about an intermittent or backout)]

Bisection shows that this is a regression from bug 1446961.

Steps to reproduce (Linux, Windows at least):
Middleclick somewhere on unlinked content.

Actual result: Autoscroll indicator offset to the right.

Expected result: Autoscroll indicator shown at click position.