I can’t delete the custom ticket fields.
I go to http://trac3.xp-dev.com/%projectnamehere%/admin/ticket/customfields,
then check those 5 default custom fields (because I don’t need them) and click “Remove selected items”.
Doesn’t matter how many I check, there is always an error like this:
bq.. Trac Error
TracError: The Trac Environment needs to be upgraded.
Run "trac-admin /server/trac-projects/%projectnamehere% upgrade"
p.
And I have to go to Project Owner Options -> Upgrade Trac every time I try this.
How do I remove those custom fields?

P.S. looks like the text formatting also doesn’t work...

Edit: also, every time you do Upgrade Trac, it creates this Wiki page: TimingAndEstimationPluginUserManual