Yep, I ran into this. It really soured me on signal, I definitely disabled it as my default SMS. I have a history of combined SMS and signal messages trapped on

Yep, I ran into this. It really soured me on signal, I definitely disabled it as my default SMS. I have a history of combined SMS and signal messages trapped on one phone. I can read them in the signal app, make backups, but not import them on a new phone. Even if the backup works, the process is rather tricky. You have to get the backup file into a specific directory on the new phone BEFORE you open signal. There's no "import from backup option". If you mess up, you have to uninstall, then do the file copy. There are issues like this going back years.