Can you use Signal on a Linux phone? I know there’s a desktop Linux client, but it relies on being activated from an Android or iPhone app to function, in my experience.
www.ubuntu-touch.io/apps/ can run Android apps with Waydroid. I don’t know if Signal works with this, but Android apps run with good performance using Waydroid (I just read about it, never used it myself).
Ubuntu Touch • Linux Phone
Ubuntu Touch is the open source phone that has freedom and privacy in mind. Supported by dozens of devices, with installer for FOSS fans