Whisker menu doesn't register hover and drag events properly

[Adrian]

1. Moving the mouse pointer into the edges of the screen, where the Whisker-menu button resides, causes it to flicker between the hovered/unhovered states, randomly falling into either following mouse inactivity. The expected behavior from prior releases is that it stays hovered (allowing the user to open it with a click).

Placing the Xfce panel at the bottom of the screen, I noticed that moving the mouse against the bottom-edge (but keeping it away from the left-edge) doesn't cause the issue like it does when placed at the top. Maybe that's related to how the coordinates are computed/constrained.

2. Dragging items within the Whisker menu (e.g. to re-order the Favorites list) doesn't work reliably. Most of the time, the picked-up items are dropped as soon as the cursor is moved. With some care and luck, a drag & drop can succeed, but no pattern/method is apparent.

ProblemType: Bug
DistroRelease: Ubuntu 17.10
Package: libxfce4panel-2.0-4 4.12.1-1ubuntu1
ProcVersionSignature: Ubuntu 4.12.0-13.14-generic 4.12.10
Uname: Linux 4.12.0-13-generic x86_64
NonfreeKernelModules: nvidia_uvm nvidia_drm nvidia_modeset nvidia
ApportVersion: 2.20.7-0ubuntu1
Architecture: amd64
CurrentDesktop: XFCE
Date: Tue Sep 5 03:52:40 2017
EcryptfsInUse: Yes
ExecutablePath: /usr/lib/x86_64-linux-gnu/xfce4/panel/wrapper-2.0
InstallationDate: Installed on 2017-09-04 (0 days ago)
InstallationMedia: Xubuntu 17.10 "Artful Aardvark" - Alpha amd64 (20170823)
SourcePackage: xfce4-panel
UpgradeStatus: No upgrade log present (probably fresh install)

[Malysps-4 (malysps-4)]

Created attachment 7078
video showing this issue

Hello. I'm using Whisker Menu 2.1.2 on Xubuntu 17.04 with xfce4-panel 4.12.1

My issue is that Whisker Menu button loses its highlight when I move cursor on the screen edges. I've tested it when the panel was pinned to the top (default in Xubuntu) and to the bottom with 100% length and on fresh user account. It seems that WM should be the first item on the panel to see this issue appear. No matter if it's displayed as an icon or a text. When the highlight is lost clicking on the button is not bringing the menu up. It just makes the highlight appear, nothing more.

I recorded my screen to explain this issue better (I will attach the file also):
https://drive.google.com/open?id=0B8qh4-wxxEZ7ckpic29mdUEyWW8

[Malysps-4 (malysps-4)]

Created attachment 7079
video showing this issue (ZIP)

[David Pearson (akxwi-dave)]

I Can confirm this seems to affect installs on Hardware rather than VM's.

[Graeme Gott (gottcode)]

This is not a bug in Whisker Menu, as I can recreate this with other plugins (such as the PulseAudio plugin and the DateTime plugin). I also can only recreate it with GTK3 plugins, and for me they do not need to be the first item on the panel. It is most likely a bug in the panel.

[Malysps-4 (malysps-4)]

This may not be related, but I think I should mention it. I can observe very similar behaviour with Plank docked to the left side of my screen, as seen here - https://drive.google.com/open?id=0B8qh4-wxxEZ7b3ZTZ0stb1VvdGM

So maybe not only xfce4-panel is affected by this bug, but all docked (GTK3) windows/objects?

[Launchpad Janitor (janitor)]

Status changed to 'Confirmed' because the bug affects multiple users.

[Ragnar Dunbar (zaroff)]

The bug is still present in Ubuntu 18.04. I have not noticed the flickering-bug of the whisker-menu button in the top left corner in any other xfce-distro but Xubuntu.

[Pasi Lallinaho (knome)]

I can't reproduce this in Xubuntu 18.04 (panel version 4.12.2). I tried with multiple different panel settings and both left/top positioning.

In case there isn't anything else to work on, the only difference we found out with the original reporter is GPU/graphic drivers; they are using Nvidia, I'm using Intel.

[Spass (spass)]

I'm the original poster (new account) and now I know a little bit more about this bug. It's not only Xfce4-panel issue, but I have no idea where it should be moved. I've created a thread on the Xfce official forum and this issue was confirmed by other user using AMD graphics card, so it seems that it's not related to a specific hardware.

Here's the link to the forum: https://forum.xfce.org/viewtopic.php?id=12190

[Spass (spass)]

I think you can close this bug report, it's not Xfce specific. It occurs on MATE, KDE and GNOME too. Unfortunately I still have no idea what causes it.

Details here: https://askubuntu.com/questions/1034051/what-causes-an-issue-with-desktop-elements-losing-focus-when-i-move-my-mouse-cur

[Adrian (thehim)]

I'm now using 18.04, and the bug (both in my case) persists.

[Theo Linkspfeifer (lastonestanding)]

I suggest filing a separate report for the drag&drop issue.

[Theo Linkspfeifer (lastonestanding)]

According to bug 1764204, some other panel plugins are affected also.

[Ubuntu QA Website (ubuntuqa)]

This bug has been reported on the Ubuntu ISO testing tracker.

A list of all reports related to this bug can be found here:
http://iso.qa.ubuntu.com/qatracker/reports/bugs/1715037