I have installed shutter by using this command in ubuntu 21.04
sudo add-apt-repository ppa:linuxuprising/shutter
sudo apt-get update
sudo apt install shutter
or
sudo snap install shutter
shutter installed but the selection option to take screenshot of something specific is disabled.
I have used it earlier with ubuntu 18.04 and 20.04 but it does not work in 21.04