"Save on focus loss" Editor Setting causes stack overflow.

[HaruYou27]

Godot version

v4.0.2.stable.mono.official [7a0977c]

System information

Kubuntu 22.10

Issue description

Godot crashed with error:
ERROR: Task 'save' already exists. at: add_task (editor/progress_dialog.cpp:177) Stack overflow.

Steps to reproduce

1. Editor Settings -> turn on Save on focus loss
2. Switch to another window.

Minimal reproduction project

This is an Editor bug.

[Calinou]

• Related to Cannot quit the editor with ALT-F4 or CTRL-Q when "save on focus loss" is active #55947, Yield causes an error if save_on_focus_loss is true #57805 and "Parent node is busy setting up children" on focus loss when save_on_focus_loss option is enabled #73765.

[HaruYou27]

I managed to get more info on the error.
Something is constantly adding Saving popup Progress bar and caused a stack overflow.
ERROR: Parent node is busy setting up children, `add_child()` failed. Consider using `add_child.call_deferred(child)` instead. at: add_child (scene/main/node.cpp:1138) ERROR: Condition "!is_inside_tree()" is true. at: popup_centered (scene/main/window.cpp:1468) ERROR: Task 'save' already exists. at: add_task (editor/progress_dialog.cpp:177) ERROR: Task 'save' already exists. at: add_task (editor/progress_dialog.cpp:177) ERROR: Task 'save' already exists.

[HaruYou27]

On Windows 7, the console still throw
ERROR: Parent node is busy setting up children, `add_child()` failed. Consider using `add_child.call_deferred(child)` instead. at: add_child (scene/main/node.cpp:1138)
ERROR: Condition "!is_inside_tree()" is true. at: popup_centered (scene/main/window.cpp:1468)
every time I switch window but does not crash.

[Calinou]

• Duplicate of "Parent node is busy setting up children" on focus loss when save_on_focus_loss option is enabled #73765.