When the History » Purge… command is executed, the following window appears:
You may select the way you want to purge a history.
- Purge redo tail - all phantom operations (or operation tail) are dropped and removed.
- Purge branches - all branches except the current one are dropped and removed.
- Clear history - all operations in a history are deleted. The document state is NOT changed, all modifications are "merged" into the single operation, which becomes an operation list root.
- Purge all - remove all operations except the very first one. In most cases (if Clear History command was not used), this root operation is "Open" or "New".
Purge History operation cannot be undone.