Reinstalling will not rebuild preferences, which is the first line of defense against irksomeness.
Quit out of InDesign and then open it again while holding down the Control, Alt, and Shift keys (Command, Ctrl, Option, and Shift on a Mac). When you get the "Delete Preferences?" alert, release the keys and click yes/ok.
Try that ...
This worked, however it also reset all my preferences... Oh well, it's better than dealing with that horrible bug! Thank you!
This didn't work, so I either have a different problem or there's something stubbornly holding on to preference settings on my Mac.
I'll be typing along in a text box, and then suddenly the text disappears below the previous line. If I stretch out the text box wider, the text reappears, but this of course solves nothing.
I've restarted the computer, restarted the app, checked for updates, checked the paragraph formatting, the character formatting, looked for hidden codes, looked for hidden objects, and there is no explanation. I mention this for future reference in case it helps someone else, because I obviously can't wait for solutions here. I'll have to do the document in another program.
Update: I'm not sure I understand the nature of the problem, but I was given a solution.
The solution was to hit the "clear overrides" button on the paragraph styles dialog box, as in the pic below.
I still don't know what caused the conflict. I'll tell you what I did in case it helps someone else. In the course of editing within this text box, I had used two or three paragraph styles, and I'd also used the "no break" setting in character settings. In trying to fix the problem, I'd checked my paragraph styles looking for something that was, perhaps, causing text to wrap off the page. I found nothing. Cutting and pasting into a different document didn't help either. Some combination of actions caused the problem.
It's working now.
This is another weird issue I have (mostly when running a second monitor...I would blame the GPU, but it's off w/ my second monitor)...I prefer to rebuild my Mac's preferences before trashing ID's (not sure if there's an equivalent process on the PC). That seems to fix it.