If you don't want to trust any client, you can write your own, it's quite simple! or audit one that's open source, I think they basically all are .
Other than that you should be fine, i think there is more risky stuff running on your machine.
As far as umbrel goes, i heard that it's communication is unencrypted, and basically relies on your network not being compromised ( if it's on the same network as your public Wi-Fi, that's probably not great). So maybe running it in a separate network and using vpn to Access it might be a good idea. I don't know enough about that though, so please don't take my word for it.
If you don't want to trust any client, you can write your own, it's quite simple! or audit one that's open source, I think they basically all are .
Other than that you should be fine, i think there is more risky stuff running on your machine.
As far as umbrel goes, i heard that it's communication is unencrypted, and basically relies on your network not being compromised ( if it's on the same network as your public Wi-Fi, that's probably not great). So maybe running it in a separate network and using vpn to Access it might be a good idea. I don't know enough about that though, so please don't take my word for it.