Recently (perhaps the past 2 months), I've had a recurring issue while doing markups in Preview. After I create a text box and type some text, if I want to go back to that text box to add or edit text, when I double-click to place my cursor in the box, the box resizes into a single insanely long line (thus running way off the edge of the page/window).

so, I need to use the corner re-size drag to narrow it down as much as I can on that page, then slide it over to the edge, and resize again; repeat as needed, depending on how long the original text in the box was.

Any clues??