Text objects vs. text in text frames
Text in Dorico Pro can exist as a text object, added to individual staves or as system text, and in text frames, which are fixed to the page rather than the music.
You can tell the difference between text objects and text in text frames by clicking them once: if the text appears highlighted with an attachment line to a staff, it is a text/system text object. If the text does not appear highlighted or has no attachment line, it is in a text frame.
You can edit both types of text in the same ways, but you can only use text tokens in text frames. You cannot use tokens in text added to staves/systems.