Deleting ticket changes which are spam

Here's how I deleted a bunch of spam links added by the user 'seekgzl' in one go:

 cd /group/project/proofgeneral/data/trac-project-env/db/
 sqlite3 trac.db
 delete from ticket_change where author='seekgzl';

or for spam tickets:

  delete from ticket where id='395';

The ​TicketDeletePlugin is supposed to provide an interface to help delete tickets or ticket changes, but my attempt to install it didn't work and is now installed. The 'delete' button should appear beside tickets when logged in as an administrative user.