1. Open "data/samples/CLUSTALW/COI.aln".
2. Select some region in the sequence area. Try to drag it.
3. Do not release the left mouse button, call context menu with the rignt mouse button.
4. Release left mouse button.
Now you have two ways:
5.1 Close context menu by the ESC key. Try to insert gaps into the selected area with SPACE.
Expected state: Gaps are successfully inserted.
Current state: nothing happens, undo and redo buttons are disabled (if they should be enabled), UGENE ignores the next mouse click.
5.2 Select in the context menu any modifying action, e.g. add new sequence to the msa.
Expected state: operation successfully finished.
Current state: operation failed with error "Can't create a common user modifications step, previous one is not complete!".