[Bug]: Text edit boxes do not display text added at the start, if the text is already longer than the box

[merni-ns]

Version of OpenTTD

Nightly 20240323, Windows 11

Expected result

Text edit boxes show the text actually entered.

Actual result

Text edit boxes do not show text inserted at the beginning, if the existing text is already longer than the box.

Steps to reproduce

1. Open any GUI with a text edit box (such as save game window, train renaming, group creation/renaming, ...)
2. Enter enough text to exceed the size of the box ("w" is useful for this):
   
3. Use the arrow keys to go back to the start and enter some letters at the start. Note that these letters aren't displayed in the edit box.
4. Save the text and notice that the inserted letters actually get saved: