when i try to get the commands done in the CLI while following this guide: Signal Messenger
I get this error when running sudo commands:
E: Type ‘sudo’ is not known on line 1 in source list /etc/apt/sources.list.d/signal-xenial.list
E: The list of sources could not be read.
Could I get some assistance… I’m still new to linux and qubes
Hi, I’m on Qubes 4.2.3 / Fedora 41. I was able to install the signal messenger using snap.
On the templateVM
On the AppVM
Hope this helps 
Seems like you made a mistake with this line:
echo 'deb [arch=amd64 signed-by=/usr/share/keyrings/signal-desktop-keyring.gpg] https://updates.signal.org/desktop/apt xenial main' | sudo tee -a /etc/apt/sources.list.d/signal-desktop.list
You can check the file content, it should be exactly:
deb [arch=amd64 signed-by=/usr/share/keyrings/signal-desktop-keyring.gpg] https://updates.signal.org/desktop/apt xenial main
Thank you everyone for your help. It turned out that for some reason the default debian template made when installing Qubes just wasn’t giving me the correct permissions to run the commands in the terminal.
THE SOLUTION: was to create a brand new debian template vm. Once I did that, I opened the template terminal, ran the commands, shutdown the qube. Created an AppQube based off it and chose Signal in the application list.
It was way too easy once I just started from scratch. I hope this info helps someone in the future.
Sorry but I still believe that there was an error in the file you created, not the ˋsudoˋ command, neither the template:
E: Type ‘sudo’ is not known on line 1 in source list /etc/apt/sources.list.d/signal-xenial.list
E: The list of sources could not be read.
Is quite explicit, if you still have the old template, please check this file content. I was able to install signal in a copy of the original debian template from the installation.
If I’m wrong it could be an interesting bug to report.