[Bug] Can't undo indentation in pattern editor

[arcusmaximus]

Operating System

Windows

What's the issue you encountered?

Pressing Ctrl-Z after indenting a piece of text moves the cursor back but does not actually undo the indentation.

How can the issue be reproduced?

• Type a letter in the pattern editor.
• Place the cursor before the letter and press Tab to indent it.
• Press Ctrl-Z. The cursor jumps back to the start of the line, but the letter stays indented.

ImHex Version

Nightly "Aug 8 2025 at 17:14:26"

ImHex Build Type

• Nightly or built from sources

Installation type

Portable

Additional context?

No response

[Naheulf]

Can reproduce with ImHex Nightly "Aug 3 2025 at 06:53:53" windows zip
Can reproduce with ImHex 1.37.4 Windows MSI.
But cannot reproduce with ImHex 1.37.1 Ubuntu deb (Ctrl+Z don't do anything)

Also note if you use Ctrl+Z twice imhex will remove one space. And if you follow it with a Ctrl+Y it will insert the letter at the start of the line.
With few more tests it seem to behave as if it remember what is done on each column, but the tab broke everything as it used many columns in one step.

[paxcut]

Tabs were never recorded for proper undo/redo operations in the text editor so this issue can probably be trace down to the original text editor code. Undo/redo operations are recorded one at a time as they occur and the recording does not depend on how many rows or columns the editing operation involves. I have added proper undo-redo support for all tab operations which include normal tab (TAB), selection tab (TAB while text is selected) and de-tab (shift-TAB). Please test it when it is convenient after the next nightly is built and let me know if problems persist.