Bug 515164

Summary: Regression: Drag-and-drop performance issue when moving a large number of images
Product: [Applications] dolphin Reporter: fabrice salvaire <fabrice.salvaire>
Component: generalAssignee: Dolphin Bug Assignee <dolphin-bugs-null>
Status: REPORTED ---    
Severity: major CC: dolphin-bugs-null
Priority: NOR    
Version First Reported In: 25.12.1   
Target Milestone: ---   
Platform: Fedora RPMs   
OS: Linux   
Latest Commit: Version Fixed/Implemented In:
Sentry Crash Report:

Description fabrice salvaire 2026-01-27 18:50:58 UTC
SUMMARY
This is a regression issue !
Dolphin freezes when we drag-and-drop a large number of images.

STEPS TO REPRODUCE
1. Split the view
2. Select a large number of images, e.g.100 in the first view
3.  Drag-and-drop to a folder in the second view

OBSERVED RESULT
Dolphin uses a lot of CPU and freezes.
It is related to the number of selected images, more it is large more it freezes.
Beyond a certain number of images, it is no longer possible to achieve a drag-and-drop.
A workaround is too select a smaller number of files and repeat...

EXPECTED RESULT
I suspect the fancy thumbnails features to be badly implemented and only tested for a few files.

SOFTWARE/OS VERSIONS
Linux/KDE Plasma: Fedora 42
KDE Plasma Version: 6.5.5
KDE Frameworks Version: 6.22.0
Qt Version: 6.9.3

ADDITIONAL INFORMATION