Single [indent] not working properly in RichTextLabel

[dalexeev]

Godot version

v4.0.beta.custom_build [61021c0]

System information

Kubuntu 22.04

Issue description

A single [indent] (or push_indent) is handled incorrectly (indented only after \n) if there is another open Item before it. However, if [indent] is the first one, or there are multiple [indent], then the indentation is correct.

In particular, this bug can be seen in Editor Help:

Steps to reproduce

BBCode	Result	Comment
[indent]123 456		Correct.
[u][indent]123 456		The bug.
[indent][u]123 456		Correct.
[u][indent][indent]123 456		If there is more than one [indent], then it is correct.
[u][indent] 123 456
000[u][indent]123 456		Is this also a bug? What should be in this case?
[u][indent][u]123 456

Minimal reproduction project

No response

[Calinou]

Can you reproduce this in 3.5 (which uses an entirely different RichTextLabel implementation)?

[dalexeev]

Can you reproduce this in 3.5 (which uses an entirely different RichTextLabel implementation)?

In 3.5, this bug is not reproduced, regardless of the order of [u] and [indent]. The penultimate case (adding a line break before [indent]) works the same as in 4.0-dev.

[dalexeev]

The bug is still reproducible in d2699dc, but in Editor Help it is no longer visible. Probably something has changed recently.