Folder status randomly gets stuck at "Scanning 99%"

[eugenesan]

Relevant components

• Standalone tray application (based on Qt Widgets)
• Plasmoid/applet for Plasma desktop
• Dolphin integration
• Command line tool (syncthingctl)
• Integrated Syncthing instance (libsyncthing)
• Android app or mobile UI in general
• Backend libraries

Syncthing Tray version or commit

Version 2.1.1 and older are affected.

The issue is not new and randomly affects folders with files in the thousands.

Qt versions

Qt 6.10.2 / Kf 6.24 / Plasma 6.6.4
Though older versions also affected.

C++ compiler, standard library and version

gcc version 15.2.0 / libc 2.43 / stdc++ 16-20260322

Platforms

Linux amd64

Desktop environments (leave blank if not applicable for the platforms)

Kubuntu 26.04 X11

Bug description

Folder status randomly get stuck at "Scanning 99%" while syncthing web interface shows the correct status.
Requesting rescan or even restarting the syncthing doesn't help.
Only restarting the plasma shell resolves the issue.

Steps to reproduce

The issue is random and not easily reproducible.

Expected behavior

Folder status should always follow what Syncthing reports

Screenshots

No response

Additional context

No response

[Martchus]

The issue is random and not easily reproducible.

I think I was also able to reproduce it once or twice a while ago but not reliably enough to be able to debug and fix it. So far I suspect that some event from Syncthing is missed or not emitted in the first place by Syncthing itself.

Only restarting the plasma shell resolves the issue.

It helped to re-connect via the button in the connection settings when I was able to reproduce the issue. You can try this the next time.

[eugenesan]

The issue is random and not easily reproducible.

I think I was also able to reproduce it once or twice a while ago but not reliably enough to be able to debug and fix it. So far I suspect that some event from Syncthing is missed or not emitted in the first place by Syncthing itself.

Only restarting the plasma shell resolves the issue.

It helped to re-connect via the button in the connection settings when I was able to reproduce the issue. You can try this the next time.

I understand. random issues can be hard to fix.

Reconnecting resolves the issue.
Though I am confused why re-connecting helps while restarting syncthing doesn't...