The inability to paste a password is probably meant as a safety measure. I can imagine however that it is counter-productive if you want to use more complicated passwords.
Fooling the system
BUT, with the option below, we can fool the system a bit and make it believe you typed the password yourself, but you actually pasted it in an intermediate window.
How it works in practice:
- First you click in the the entry-box (password entry) of the desktop app's window.
Then you press a key combination of your choice (set in System Settings, see further below) to call a small window, in which you can paste your complicated password:
Click "OK", your password will be "typed" in the entry-box of the desktop app.
How to use
The script uses xdotool
sudo apt-get install xdotool
Paste the script below into an empty file, save it as paste_password.py
Add it to a shortcut key of your choice: Choose: System Settings > "Keyboard" > "Shortcuts" > "Custom Shortcuts". Click the "+" and add the command:
python3 /path/to/paste_password.py
The script
#!/usr/bin/env python3
import subprocess
import time
try:
command = 'zenity --entry --text "Password" --title "Password paste"'.strip()
passwd = subprocess.check_output(["/bin/bash", "-c", command]).decode("utf-8").strip()
except subprocess.CalledProcessError:
pass
else:
time.sleep(0.5)
subprocess.Popen(["/bin/bash", "-c", "xdotool type '"+passwd+"'"])
