Relabel Zenity Cancel button

You can relabel the button but you can’t remove it:

$ zenity --list --cancel-label="Go Back" --column="Column 1"

Will give you:

YAD (Yet Another Dialog)

Both yad and zenity allow you to use GUI dialog boxes from a bash script or the shell command line. Yad surpasses Zenity in every department though:

sudo apt install yad

Works in all distros.

Yad Progress bars

You can define multiple progress bars in yad where zenity only offers 1. You can also include scrolling text.

Yad buttons

You can assign any text you want to any button. Also notice you can include a Window icon too.

Yad text entry

Yad displays text for you to change. Zenity cannot display existing text you can only enter new text.

Yad support

The author of Yad and many more contributors answer your questions in google groups. I’ve posted four or five questions about advanced functionality and usually get an answer within 24 hours. Not to mention enhancements are provided through the same channel.