Hi smolgrrr,
I access the umbrel on Firefox most of the time using Tailscale.
To give it a try I accessed it via Tor browser, took quite a long time, however that worked as it should.
When I now go back and use it again via FF it (magically) works, but I really don´t have a clue why it does now and not before…
Another thing, I noticed on the offers page it´s not possible to select other hosts which gives a very limited choice compared to what´s normally offered there.
I assume accessing it via the client is still experimental, but it´s interesting and I will keep an eye on it.
From what I understand, many Robosats features on the backend are only enabled to work over TOR. I can’t find a good reference for it, but this should give you a rough idea Accessing RoboSats - Learn RoboSats