Custom operations are not added to undo stack

Phenomenon

When using preventDefault() and implementing custom editing operations, those operations are not added to the browser’s undo stack. Users cannot undo custom operations using Ctrl+Z.

Reproduction example

1. Implement custom text insertion with preventDefault()
2. Insert some text
3. Press Ctrl+Z to undo

Observed behavior

• Custom operation is not undone
• Browser’s undo stack does not include the operation
• User cannot undo custom operations
• Undo/redo functionality is broken for custom features

Expected behavior

• Custom operations should be undoable
• Undo stack should include all operations
• Ctrl+Z should work for custom operations
• Redo should also work

Browser Comparison

• All browsers: Custom operations not in undo stack
• This is expected behavior when using preventDefault()
• Custom undo/redo implementation needed

Notes and possible direction for workarounds

• Implement custom undo/redo stack
• Save state before each operation
• Restore state on undo
• Handle Ctrl+Z and Ctrl+Y manually
• Maintain separate undo/redo stacks