I think they appeal to powerusers that probably already use a client like Thunderbird. :) However, their webmail client is just RainLoop, which you can find a demo of here: https://www.rainloop.net/try-now/

Also, they are currently collaborating with sourcehut to develop a new webmail client to replace RainLoop. For the record, I like RainLoop quite a bit and find it to be very speedy.

Sure, but as a poweruser with a surname domain I have to be considerate of all none-poweruser relatives that are going to be using it.

So even though I'll barely use it at all I signed up for Migadu only so that I could have a look at the webmail UI. But I couldn't even get a look at it, likely because I have yet to configured my domain. But I will not disrupt my domain just to get a peak at the UI...

Thanks!

No problem. Not sure if you noticed, but I mentioned they use Rainloop for their webmail, which I provided a link to a demo of if you're just interested in checking out the webmail UI.