You can uninstall Textmode the same way you would uninstall any other standard macOS app.
Quit the Textmode app
on your Mac.
In the Finder, move Textmode to the Trash.
To uninstall Textmode and remove all related files, delete the following files and folders:
/Applications/Textmode
~/Library/Containers/com.tidymachines.textmode/
~/Library/Application Scripts/com.tidymachines.textmode/
Here, the tilde (~) represents your home folder and the slash (/) means the folder separator.