Editing issues: cursor jumps, Shift+Tab unindent fails, and syntax highlighting flashes

[EmilioGiordano]

Environment

• App: Athas 0.6.0
• OS: Windows 10.0.19045

Problem

Editing in the editor behaves incorrectly. While typing, the cursor sometimes jumps to unexpected lines. Shift+Tab also does not unindent as expected. In addition, syntax highlighting/colors appear to flash or change briefly while typing.

Steps to reproduce

1. Open any file.
2. Start typing normally.
3. Press Tab and Shift+Tab.
4. Observe the cursor position and the syntax highlighting while editing.

Expected result

• Typing should insert text normally without unexpected cursor jumps.
• Shift+Tab should unindent the current line or selection.
• Syntax highlighting should remain stable while typing.

Actual result

• The cursor sometimes jumps to random lines while typing.
• Shift+Tab does not perform the reverse-tab/unindent action.
• Code colors briefly flash or change while typing.

Showcase video

Note: The video was filmed on a previous version to 0.6.0, but after updated it, it worked exactly the same.

2026-05-15-11-09-30.mp4