@Mic_ I don't know the specifics about Arch/Manjaro
But I hope it's the same and you should have inputs in
/var/log/syslog or with
dmesg command when you plug the phone.
So try this :
1- run the following command :
tail -f /var/log/syslog
2- plug your phone in
3- wait until the error message (the popup you posted)
4- Ctrl-C to stop the tail command
5- run the following command in another terminal :
If it's OK, you can copy the whole output from the first command and the end of the other one so we can have a look.
If you have an error on one of the command then it's probably because your OS doesn't handle the logs the way I'm used to, so it'll require some internet search or someone who knows manjaro/arch.