Improvement destription
SubclassSelectorDrawer, lines 60 to 64 adjust foldout rectangle horizontal position by 12 units to the left for versions 2022.2 or newer like so:
#if UNITY_2022_2_OR_NEWER
// NOTE: Position x must be adjusted.
// FIXME: Is there a more essential solution...?
foldoutRect.x -= 12;
#endif
which actually makes it render almost outside of the inspector in 2022.3:

Removing this adjustment makes the foldout render correctly in 2022.3.
If I find the time, I'll do a PR
Improvement destription
SubclassSelectorDrawer, lines 60 to 64 adjust foldout rectangle horizontal position by 12 units to the left for versions 2022.2 or newer like so:
which actually makes it render almost outside of the inspector in 2022.3:

Removing this adjustment makes the foldout render correctly in 2022.3.
If I find the time, I'll do a PR