I've conducted Trac trunk testing lately and installed TagsPlugin into a fresh environment created and used with Trac t:r10850.
The plugin constantly failed to create the required db table tags:
Traceback (most recent call last):
File "<shortened>/Trac-0.13dev_r10849-py2.6.egg/trac/env.py", line 810, in open_environment
needs_upgrade = env.needs_upgrade()
File "<shortened>/Trac-0.13dev_r10849-py2.6.egg/trac/env.py", line 646, in needs_upgrade
File "build/bdist.linux-i586/egg/tractags/model.py", line 23, in environment_needs_upgrade
File "build/bdist.linux-i586/egg/tractags/model.py", line 47, in _need_migration
File "<shortened>/Trac-0.13dev_r10849-py2.6.egg/trac/db/util.py", line 107, in __getattr__
Note: <shortened> has been edited by myself for traceback readability. The code resides in a virtualenv, but that seems to be unrelated here.
Never seen that before, and especially the empty error looks suspicious.
Not only it renders the whole plugin unusable but consequently leaves ugly traces in Trac itself like 'OperationalError: no such table: tags' everywhere tags are expected, like every wiki page.
Hint: Trac version reference below should be read as 0.13dev.