huge frame-drops with AnimatedSprite (WindowManager bug)

[azur-wolf]

Godot version

3.5.0

System information

Linux Debian 11, Gnome 3.38.5 (Wayland), GLES3, Intel HD Graphics 4400 (HSW GT2)

Issue description

When Play a project inside the editor, it starts slow, like huge frame-drops.
It is 2D with some sprites, so it shouldn't be any performance issue.

It keeps indefinitely with the slowdown, until pressing a hotkey to switch virtual desktop (either the view or moving a window to another one).

Have taken a screenshot with the Profiler:

The high plateau is the frame-drop. After doing virtual desktop switching, things become stable.

Thought that it was because of Wayland, but tried on a X11 session, and also happens the same.

The cause is the AnimatedSprite is playing from launching the project (marking the property in the inspector), even if it only has a single animation with few sprites.

Also in my case, throws a couple of WindowManager errors:

Steps to reproduce

(it can be dependent on the OS and WindowManager)
Linux Debian 11
Gnome 3.38.5 (Wayland & XWayland)
using multiple virtual desktops (2 in my case)

1. Download and launch (F5) the attached project. (notice the fps label)
2. now press a hotkey that let you switch between your virtual desktops [OS description above]
3. notice the fps become stable, press Esc to close
4. Now un-check the AnimatedSprite.playing property from the inspector, and run the project again.
5. now fps should be stable
6. press Enter to toggle AnimatedSprite.playing (see script)
7. fps should stay stable even if the animation is running.

[if you're doesn't experience frame-drops, maybe is related to the errors in the last image]

Minimal reproduction project

framedrop_virtual_desktops.zip