I've been wanting to link my Android tablet to Signal for ages now and recently came across Molly as an alternative app to use, which allows this possibility.
To import a backup from Signal you must use a matching or newer version of Molly, though, and where Molly is 6.41.3-2, Signal is 6.43.2, so I'll have to wait a bit before I can switch, I suppose. Looking at the open issues on Github though, it seems linked devices aren't all that stable yet.
How are your experiences with Molly, if you have them?
(I came across this disclaimer too: "unofficial forks are not supposed to use Signal’s infrastructure so Molly violates Signal’s TOS".)
The last time I did it, I was euphoric and more emthatic than I normally am.