In Graph Builder charts I frequently place text box annotations on top of the charts. When I add more charts, change the scale, or resize anything, I notice the annotation moves around and resizes itself automatically to try to stay where it thinks I want it to be. But I find that the annotation never ends up where I want it, so I have to go move it again manually anyway. Also, when the annotation text box resizes itself, it sometimes shrinks to a tiny sliver. The text is still visible, but it is impossible to click on it to resize it or delete it.
I think the Text Box feature needs to be fixed so it never allows the text box to be shrunk to zero width or height. I would consider this a bug. After this happens it becomes impossible to change or remove the text boxes using the GUI; you basically have to start over and rebuild the graph. Of course, you always can "save script to data table" and then edit the script to remove the offending text boxes, but this is not very user-friendly.
It would also be nice if we had an option to lock the size and position of a text box (or line, shape, etc...) so it does not move or resize with the chart underneath it.