Save or clear embedded undo history

Control whether history travels with the project file independently of session undo.

Use

User Preferences > General offers Save undo history with save file. Turning it off removes embedded history on the next save; undo remains available in the session. Clear undo history from save file acts on the current saved project and also disables future embedding. Save the project first if it has no path.

Effect and caveats

Clearing saved history does not clear current session undo. Retention controls still limit stored entries. Project schema upgrades preserve the working drawing but discard old saved undo history and checkpoints; do not rely on migration to retain revisions. Keep independent project copies when you need durable version archives. See [ Undo history retention limits ], [ Save and Save As ], and [ Autosave preview and recovery ].