Comment 13 for bug 336866

Argh, this is a nuisance. It also happens in this code:

        bug = self.launchpad.bugs[id]
        bug.newMessage(content='This crash has the same stack trace characteristics as bug #%i. \
However, the latter was already fixed in an earlier package version than the \
one in this report. This might be a regression or because the problem is \
in a dependent package.' % master,
            subject='Possible regression detected')
        bug.tags = bug.tags + ['regression-retracer'] # LP#254901 workaround

        print bug._dirty_attributes # confirms that .tags is dirty
        bug.lp_save() # causes HTTP Error 412: Precondition Failed