To Replicate:
Create a prompt meme or gift exchange challenge
In Request Settings, set
all Required and Allowed to 0 for all tag types
Description to allowed (should be pre-selected)
In the Tag Options section, set
Tag Sets to Use: blank
Character Settings: check Fandom Only
Relationship Settings: check Fandom Only
Submit.
Navigate to the Prompt or Sign-up Form and attempt to sign up. Note that you have to actually enter something in the Request section’s “Description” field to trigger the error described in the issue. If you enter nothing, you get a standard, “Sorry! We couldn't save this challenge signup because…” error.
Admire the browser-formatted 500 (Chrome 78 on Windows) or blank white page (Safari 13 on Mac), depending on your browser.
What should happen:
It should allow you to save the sign-up, just like it does if you set the Allowed tags to a number greater than 0.