Tested versions

Reproducible in 4.5rc1
Not reproducible in 4.4.1 stable.

System information

Godot v4.5.rc1 - Windows 11 (build 26100) - Multi-window, 2 monitors - Vulkan (Forward+) - dedicated NVIDIA GeForce RTX 2060 (NVIDIA; 32.0.15.7700) - AMD Ryzen 7 5700X 8-Core Processor (16 threads) - 31.89 GiB memory

Issue description

This came up in testing after reporting on this bug:
#108423

In 4.5, If I try to make text appear in a RichTextLabel which has horizontal justification set to RIGHT, and i move the Visible Ratio while text is set to "Characters Before Shaping", it still makes the text appear from the left. This was not the case in 4.4, which had text appear from the right even as I was growing it with Visible Ratio.

For the record, only "Characters Before Shaping" achieved the desired effect in 4.4, and trying other modes in both 4.4 and 4.5 did not replicate its functionality.

4.4:

4.5rc1

The same issue applies for Center alignment

4.4:

4.5rc1:

:

The fact that I can no longer achieve the first text affect at all, regardless of setting, appears to be a regression.

Steps to reproduce

In 4.4.1, open a new project and create a RichTextLabel node.
Add some text and set the Horizontal Alignment to the right.
Move the visible Ratio Slider back and forth. Notice that the new line grows from the right side of the text box.

Open the same file in 4.5rc1.
Move the visible Ratio Slider back and forth. Notice that the new line doesn't grow from the right as expected.

Minimal reproduction project (MRP)

4.4-4.5-text_content_bug.zip