It is possible to save invalid values simply by removing the HTML5 attributes
minlength in many of the fields (see my screenshot, invalid display name, email and matrix user). It is also possible to save
undefined (displayed as
---------) as a value for sort type (by removing the
disabled attribute from that option in the
select box), doing so causes the front page to time out next time you load it on a new tab or press
F5. Using a similar method you can also choose an invalid theme (and as you can see in my screenshot themes stop loading after that and you get a website without any CSS).
Edit: I removed the invalid saved sort mode and theme from my account because the website is unusable with them so you aren’t going to see them in the database. I left the invalid display name, email and matrix user in case you want to check that my report is valid.
Edit 2: also try sending me a private message, it takes forever to send.