Nautilus actions is a file manager extension allows to add arbitrary program to be launched through the context menu of selected files.
Ubuntu does no longer ship the Nautilus actions package in universe repositories since it’s been deprecated and renamed to FileManager actions.
For those still need the tool, it has made into PPA repository for Ubuntu 18.04.
1. Open terminal either via Ctrl+Alt+T keyboard shortcut or from app launcher. When it opens, run command to add the PPA:
sudo add-apt-repository ppa:daniel-marynicz/filemanager-actions
Type user password (no asterisks feedback) when it prompts and hit Enter.
2. Then run command to install the extension:
sudo apt install filemanager-actions-nautilus-extension
For Linux Mint Cinnamon or MATE desktop, you can install Nemo or Caja extension via command:
sudo apt install filemanager-actions-nemo-extension filemanager-actions-caja-extension
Once installed, search for and launch FileManager Actions to launch the tool.
To remove filemanager actions, run command in terminal:
sudo apt remove --autoremove filemanager-actions
To remove the PPA, go to Software & Updates -> Other Software.