The user interface plug-in adds commands to the right-click menu, Miles 33 Fit text to box and Miles 33 Undo fit text to box, just below the built-in Text frame options command. The extra commands will only be present when they are relevant.
The user interface plug-in also adds Miles 33 Fitting to the Window menu; this command shows a small palette with two buttons and a feedback area. The feedback is a single percentage, for example, -33% to show that the text had to be shrunk, and that 33% of the permitted adjustments were used.