ProjectSettings.save() does nothing

[MaaaxiKing]

Godot version:

3.2.3.stable

OS/device including version:

Windows 10 Home 1909

Issue description:

I wanted to save the ProjectSettings which I configured earlier with ProjectSettings.set_setting("application/run/main_scene", "res://title_screen/title_screen.tscn"), which works because when I do print(ProjectSettings.get_setting("application/run/main_scene"), I get "res://title_screen/title_screen.tscn" printed, with ProjectSettings.save(). I even disabled safe save in EditorSettings and my antivirus. For days I ask myself where the problem is.

Steps to reproduce:
in script: change any ProjectSetting and then save it.

Minimal reproduction project:

Bug_REPRODUCTION.zip

[KoBeWi]

Seems like you can't modify ProjectSettings from within running project. It works when you add tool to your script. Probably should be documented.

[MaaaxiKing]

But why does the method exist then? To me it seems like a bug.

[MaaaxiKing]

After disconnecting from my Android phone I got

E 0:10:43.140   _save_settings_text: Couldn't save project.godot - project.godot.
  <C++ Error>   Condition "err != OK" is true. Returned: err
  <C++ Source>  core/project_settings.cpp:755 @ _save_settings_text()
  <Stack Trace> tutorial.gd:36 @ next()
                tutorial.gd:29 @ _input()

. I don't know if this helps.

[MaaaxiKing]

For me, it does not work with tool.

[rsubtil]

This was fixed by #45880

[KoBeWi]

For me, it does not work with tool.

You need to call it from the editor. It won't work in the running game.

This was fixed by #45880

It's unrelated.

[rsubtil]

Sorry, I forgot to show my findings. 😅

It looks like ProjectSettings.save() works; the issue is that, as soon as the editor is re-focused, it saves the project settings, thus overriding any modifications done externally

[KoBeWi]

Ah you are right, although the PR that fixed this is #45968
I wonder if it works in exported project though.

[MaaaxiKing]

That should be documented!

[Zireael07]

No need to document something that's already fixed @MaaaxiKing

[KoBeWi]

Ok so it works in exported project too, but the modified settings can't be loaded. This might be worth mentioning in the doc.

[MikeSchulze]

This bug needs to be merged into v3.x aswell.
My inital plugin setting are not saved ;)

ah i see 'Cherry-picked for 3.2.4.' i have to try