1533693 - If the menupopup has been scrolled, the subfolder would not open when dragging over the subfolder menu.

Status: VERIFIED FIXED

(Core :: XUL, defect, P1)

Description

[Alice0775 White]

[Tracking Requested - why for this release]: break bookmarks menupopup

Reproducible: always

Steps to reproduce:
0. Prepare long bookmark menu and some folders in the menu so that the menu can be scrolled
i,e
Bookmarks(or bookmarl folder)
bookmark
bookmark
bookmark
bookmark
bookmark
bookmark
bookmark folder
bookmark folder
bookmark
bookmark
bookmark
bookmark
...
bookmark
bookmark

1. Click bookmarks menu or bookmarks folder in bookmark toolbar
2. Scroll the menupopup a little (if not scrolled, this problem does not happen)
3. Dragging a bookmark over a bookmark folder submenu

Actual Results:
The bookmark folder submenu would not open

Expected Results:
The bookmark folder submenu should open automatically

Regression window:https://hg.mozilla.org/integration/mozilla-inbound/pushloghtml?fromchange=fad9ff877c1cbd2b06c03263ba9fc91d2f1fc405&tochange=57624be2e55cefabe21feb5e0169f33b283f9ddd

Suspect: aa8dea3c0f43 Neil Deakin — Bug 1519953, replace calls to retrieve boxobject position and size with getBoundingClientRect, r=gijs

Neil, Your bunch of patch seems to cause the regression. Can you please look into this?

Comment 1

[Neil Deakin]

Attachment: Bug 1533693, just compare the drop point against event.clientY instead of using a complicated check involving scroll positions, fixes the subfolder not opening in bookmarks menu when dragging over it, r?gijs

Comment 2

[Narcis Beleuzu [:NarcisB]]

https://hg.mozilla.org/mozilla-central/rev/7b997d966c3c

Comment 3

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

https://hg.mozilla.org/integration/autoland/rev/7b997d966c3c5fad733d2255a4d57aff2237112a

Comment 4

[Anca Soncutean, Desktop QA]

I’ve reproduced the issue with Fx 67.0a1 (2019-03-08) on Windows 10 x64.
This issue is verified fixed on Fx 67.0b11 on Windows 10 x64, Ubuntu 18.04 x64 and macOS 10.13.