Hi,
Tropic:
> Hi Tails
> 
> Love your O/S.
> 
> Im trying to install Signal but I cant get it to save in persistence.  I 
> have trawled the net looking for an answer but cant find anything
> 
> It installs ok and works but wont save when Tails is restarted
I tested this documentation a while ago, it worked, but I don't if it's 
still accurate:
https://bisco.org/notes/installing-and-running-signal-on-tails/
The date of publication is not displayed on the article, but according 
to the index page it's Oct 3, 2019
Please report if you find your way,
Cheers