1771512 - Starting a horizontal scroll while in vertical overscroll can cause unintended history swiping

Status: RESOLVED DUPLICATE of bug 1773381

(Core :: Panning and Zooming, defect)

Description

[Markus Stange [:mstange]]

Steps to reproduce:

1. Click this link to open the profiler in this tab: https://share.firefox.dev/3MWESqC
2. In the activity graph at the top, click the blue part of the graph so that the call tree expands to a deep stack and you have a lot of scroll size to work with.
3. In the call tree, do a fast vertical fling upwards.
4. While the call tree does an overscroll bounce at the top edge, do a quick horizontal scroll to the left.

Expected results:
The call tree should scroll horizontally while continuing its vertical bounce.

Actual results:
The call tree "blocks" the horizontal scroll. Instead, the scroll is translated into a history swipe and you end up navigating to the previous page.

Comment 1

[Dan Robertson (:dlrobertson)]

(In reply to Markus Stange [:mstange] from comment #0)

The call tree "blocks" the horizontal scroll. Instead, the scroll is translated into a history swipe and you end up navigating to the previous page.

Does this only happen when there is no horizontal space to scroll in the given direction? I have only been able to reproduce this when there is no horizontal space.

Comment 2

[Markus Stange [:mstange]]

No, it happens with plenty of horizontal space left. That's the most frustrating aspect of it.

I'm on macOS 12. Maybe this makes a difference with respect to the types of NSEvent phases that we receive.

Comment 3

[BugBot [:suhaib / :marco/ :calixte]]

Set release status flags based on info from the regressing bug 1713403