Fix (wayfire/backend): Fixed unhandled exception (out_of_range) after…

[muratyalcin-ce]

Waybar version & Setup Info

Waybar v0.15.0
Waybar v05945748 (branch 'master')

I am launching waybar using wayfire's autostart plugin.

Explanation of the Bug

Waybar crashes with an unhandled exception after i put my laptop in idle.

After examining the logs, i found an unhandled exception in the backend code of wayfire.

Related logs:

[2026-05-27 23:06:32.550] [debug] Wayfire IPC: received event "output-wset-changed"
[2026-05-27 23:06:32.552] [debug] Output removed: Chimei Innolux Corporation 0x15E6
terminate called after throwing an instance of 'std::out_of_range'
  what():  unordered_map::at

Simply adding a try-catch clause could have unintended side effects, i apologize in advance for my lack of knowledge about the codebase.
The patch seems to work when trying to recreate the bug.
There may be a way where the proper wset might not get set and crash the program with a different unhandled exception.

I unfortunately do not have the hardware to test this with multiple outputs.
Please do point out if there are any faults within my solution as I consider myself rather inexperienced.

[muratyalcin-ce]

The patch seems to work regardless of whether or not the preserve-output plugin is loaded in wayfire. Explicitly specifiying an output in waybar's configuration also did not affect the patch negatively.