I encountered a bug where you get a red error message telling you the alias must end in @riseup.net if you enter it without the @riseup.net ending first.
The issue is you can't F**KING delete it and save the change. You just get the same message again and again. You cannot add the corrected alias over top of, below, etc. I assume the script just spits out the error message and stops without realizing the correction has been made.
The workaround is to overwrite the alias you made without the @riseup ending with completely random jibberish that does end in @riseup.net. I used "firstname.lastname@example.org". Save the change. Then overwrite that one with what you want.
1) You type joesmith.
2) You want email@example.com but didn't know the @riseup.net isn't automatically added.
3) You can't change it...
4) Highlight "joesmith" and overwrite with "firstname.lastname@example.org"
5) Hit save and look for the green "changes made" box
6) Highlight "email@example.com" and overwrite with "firstname.lastname@example.org"
7) Hit save
To Riseup Team: You guys are doing a fantastic job with the resources you have but there is absolutely NO indication anywhere that riseup.net isn't automatically added to new aliases because you know...If I'm using Riseup I kind of don't expect my alias to be email@example.com...
I don't believe in bringing issues without a solution too; so I suggest as a quick-fix to add the following message to the aliases box that can be overwritten just like the "Subject" line is for new tickets.
"Please add @Riseup.net to the end of your alias. IF YOU DON'T, IT WILL NOT WORK."