F-Droid recommends the version 19.0-alpha1 as the new stable version. I have installed it, and it is obviously unstable. It crashed immediately, and I could not even downgrade it (I had to uninstall and install the previous version).
This is a known issue:
https://github.com/westnordost/StreetComplete/releases/tag/v19.0-alpha2
And seems to be an f-droid bug, not @westnordost's fault.
On top of that, it looks like the F-Droid build bot is stuck since Friday, so the alpha2 update is not even coming through.
I added another bug report because I think the one you commented on reads a little obscure and/or the F-Droid maintainers don't understand the big issue about the field not working
"I would not consider it reliable, just a helper"
And added a forum topic regarding the build bot being stuck, if it is:
https://forum.f-droid.org/t/f-droid-build-bot-stuck-since-friday/9563
v19.0 is now on f-droid