RichTextLabel not respecting the content_margin_bottom value.

[azagaya]

Tested versions

v4.2.1.stable.official [b09f793]

System information

Windows 11 and Ubuntu 22.04, all renderers

Issue description

When adding a style to a RichTextLabel, and setting content_margin_bot, the text does not respect these margin, which causes text being rendered on top of the margins.

Example:

Steps to reproduce

• Add a RichTextLabel, fill it with text
• Add a StyleBoxFlat to it
• Set border width to 20 for all borders
• Set content margin to 30 for all borders
• Note how text overlaps with borders only in the bottom

Minimal reproduction project (MRP)

ThemeIssues.zip

[noidexe]

I noticed that as you add to bottom_margin it adds extra blank content to scroll after the text.
Here's how it looks with content_margin_bottom = 100

So it seems to be adding to the content to be scrolled rather than calculate where to clip content rendering

[noidexe]

The same problem happens with the right content margin

It works correctly when enabling "Fit Content"

Notice that the same happens with a regular label when you enable "Clip Text"

But it works correctly when "Text Overrun" is set to anything other than "Trim Nothing". Here's with "Trim Characters"

Also, you can see that setting direction to right-to-left makes results in the left content margin being ignored

What I think is happening is that the contents are rendered using the right offset as starting point, but then Clip Contents only cares about the control's rectangle even though it should consider content margins