That probably means your instance hasn’t fetched the remote community yet. Not familiar with Jerboa, but in the web you need to search in Communities > All for !nottheonion@lemmy.ml and wait a few seconds. Then the link will work. It’s a known issue with lemmy and the devs are working on it.
We need an /r/nottheonion
Not the onion@lemmy.ml should be what you're looking for
Are there supposed to be spaces in the community name?
Nope. This link should work from your local instance.
This link kills my Jerboa client
That probably means your instance hasn’t fetched the remote community yet. Not familiar with Jerboa, but in the web you need to search in Communities > All for !nottheonion@lemmy.ml and wait a few seconds. Then the link will work. It’s a known issue with lemmy and the devs are working on it.