Bug 491585

Summary:	Dragging pinned apps around sometimes changes the dragged item while still dragging
Product:	[Plasma] plasmashell	Reporter:	jakubg1.100
Component:	Task Manager and Icons-Only Task Manager	Assignee:	Plasma Bugs List <plasma-bugs>
Status:	RESOLVED UPSTREAM
Severity:	normal	CC:	4wy78uwh, dofficialgman, jlayne, kdedev, muench.rico, musicalstrength27, nate, niccolo, qydwhotmail, sebastian.pb31
Priority:	HI
Version:	6.1.1
Target Milestone:	1.0
Platform:	Fedora RPMs
OS:	Linux
URL:	https://bugreports.qt.io/browse/QTBUG-127821
See Also:	https://bugs.kde.org/show_bug.cgi?id=482770 https://bugs.kde.org/show_bug.cgi?id=491100
Latest Commit:		Version Fixed In:	Qt 6.8.1
Sentry Crash Report:
Attachments:	The problem illustration.

Description jakubg1.100 2024-08-11 17:10:03 UTC

SUMMARY
Whenever I'm trying to drag pinned apps around on the taskbar, they can weirdly jump around like shown in the video. This gets frustrating very quickly.

STEPS TO REPRODUCE
1. Pin some apps (somewhere around 10 should be enough) to the taskbar. Open some of them for good measure.
2. Open the Task Switcher settings and set the following settings:
  - Group tasks: By name
  - When grouped tasks are clicked: Show previews in small windows
  - Order: Manually
3. Try dragging a certain app from one end to the other.

OBSERVED RESULT
The apps weirdly jump around like shown in the video.

EXPECTED RESULT
The apps are dragged properly, like on Windows.

SOFTWARE/OS VERSIONS
(available in the Info Center app, or by running `kinfo` in a terminal window)
Linux/KDE Plasma: Fedora 40, kernel 6.9.7-200.fc40.x86_64 (64-bit)
KDE Plasma Version: 6.1.1
KDE Frameworks Version: 6.3.0
Qt Version: 6.7.2

ADDITIONAL INFORMATION
I'm unable to change my OS language to English or to spin up a live USB to confirm this issue on a freshly installed (or actually "not installed yet") instance of the OS, so the description might be a bit dodgy and there may be extra steps that I'm unaware of. I hope this will be enough, though, and I'm happy to provide extra information on request, as long as I'm able to do it.

Comment 1 jakubg1.100 2024-08-11 17:13:14 UTC

Created attachment 172517 [details]
The problem illustration.

Comment 2 Nate Graham 2024-08-12 16:48:09 UTC

Ok, I can reproduce this issue. It's the same issue as Bug 482770, with with a narrower scope. Looks like now it only sometimes happens, not all the time.

Comment 3 fanzhuyifan 2024-08-17 22:31:25 UTC

*** Bug 491822 has been marked as a duplicate of this bug. ***

Comment 4 fanzhuyifan 2024-08-17 22:31:35 UTC

*** Bug 491840 has been marked as a duplicate of this bug. ***

Comment 5 fanzhuyifan 2024-08-25 14:24:36 UTC

*** Bug 492161 has been marked as a duplicate of this bug. ***

Comment 6 Nate Graham 2024-08-30 22:32:23 UTC

*** Bug 492419 has been marked as a duplicate of this bug. ***

Comment 7 Niccolò Venerandi 2024-09-18 13:43:27 UTC

I cannot reproduce with the latest version of 6.7 (which will (tomorrow?) be released as 6.7.3), whereas I can reproduce on 6.7.2; I'm guessing it's been fixed. Closed as upstream, will open a upstream bug report if it shows up again

Comment 8 Niccolò Venerandi 2024-09-23 12:21:08 UTC

*** Bug 493499 has been marked as a duplicate of this bug. ***

Comment 9 Rico M. 2024-10-17 17:51:18 UTC

(In reply to Niccolò Venerandi from comment #7)
> I cannot reproduce with the latest version of 6.7 (which will (tomorrow?) be
> released as 6.7.3), whereas I can reproduce on 6.7.2; I'm guessing it's been
> fixed. Closed as upstream, will open a upstream bug report if it shows up
> again

I still have this bug on Qt 6.8.0
More specifically this one: https://bugs.kde.org/show_bug.cgi?id=493499

The problem is in the selection of which icon will get dragged. (Once an icon is being dragged, everything works as expected.)
When I want to drag and drop multiple icons (one after the other) the following happens:
  1) Drag and drop the first icon (this works as expected)
  2) When starting to drag the second icon, the wrong icon is selected as the "drag target" (i.e., not the one under the cursor)

I also tried to look into this myself but I couldn't find where the logic for this is located. I'd appreciate a hint for where to look.
Finding and fixing a bug for Dolphin was no problem but this feels much more convoluted.


$ kinfo
Operating System: EndeavourOS 
KDE Plasma Version: 6.2.1
KDE Frameworks Version: 6.7.0
Qt Version: 6.8.0
Kernel Version: 6.11.3-arch1-1 (64-bit)
Graphics Platform: Wayland
Processors: 16 × AMD Ryzen 7 5700X 8-Core Processor
Memory: 31.2 GiB of RAM
Graphics Processor: AMD Radeon RX 6700

Comment 10 Nate Graham 2024-10-22 16:19:17 UTC

That remaining issue is https://bugreports.qt.io/browse/QTBUG-127821, which has an open patch to fix it.