The ability to set the language on the user creation form could be something useful on a multi user environment.

I like how Simplepush presents a couple of different ways to generate push messages on their website:

https://simplepush.io/#libraries

How about having a similar feature directly in the server GUI? That would include the bits documented here https://gotify.net/docs/pushmsg

https://scotthelme.co.uk/a-new-security-header-feature-policy/

I guess it will be easy to add, because we certainly don't use any of these features.
Or maybe "gyroscope" or so may be used by the random number generator in sjcl, but that's all.

As mentioned in #27, the core.database method to assign a reaction role id needs a rework, along with possibly a change in the DB tables. A migration script would most likely be necessary in that case.