"ERROR: Task 'generate_thumbnails' already exists" when saving a scene.

[mgiuca]

Tested versions

• Reproducible in: 4.5.beta1
• Not reproducible in: 4.4.1.stable

System information

Godot v4.5.beta1 - Ubuntu 24.04.2 LTS 24.04 on X11 - X11 display driver, Multi-window, 2 monitors - OpenGL 3 (Compatibility) - NVIDIA GeForce GTX 1060 6GB (nvidia; 535.230.02) - Intel(R) Core(TM) i5-4570 CPU @ 3.20GHz (4 threads) - 7.69 GiB memory

Issue description

Every time I save a scene, I see in the Output panel (in red):

ERROR: Task 'generate_thumbnails' already exists.

Suspect this is to do with the new scene thumbnails generation feature added in 4.5.

Also anecdotally, saving scenes seems to take longer now (about 1 second, where it used to be unnoticeable).

Steps to reproduce

1. Open a scene.
2. Make a change to the scene (not the code), e.g. change a value.
3. Press Ctrl+S.

Minimal reproduction project (MRP)

N/A

[precup]

Are you able to reproduce this in a fresh project? I'm unable to reproduce this on a fresh project or Truck Town.

Godot v4.5.beta (46c495c) - Windows 10 (build 19045) - Multi-window, 3 monitors - Vulkan (Forward+) - dedicated NVIDIA GeForce RTX 2080 Ti (NVIDIA; 31.0.15.3713) - AMD Ryzen 9 3900X 12-Core Processor (24 threads) - 31.94 GiB memory

[akien-mga]

This was likely caused by #102313, which was reverted in #107786, so would be fixed in latest master.

[precup]

Agreed.

Noting for clarity that that commit SHA I was testing with is 4.5-beta1, so #107786 hadn't landed yet but I was still unable to repro.

[akien-mga]

Fixed by #107786.