I envision Linux next. Windows would be tricky as WebKit is not really up to date on Windows. So we would probably have to resort to a differnt rendering engine. We are long way from this though, that kind of project would probably take 20 people extra.
There is already an iOS/iPadOS version. Elsewhere, I have read that the developers would like to make a Linux version, but that they currently don’t have the manpower to do so.