I use a lot of hidden text in several templates to hide text that I may or may not need. I either delete is it unhide it as I create the document.

Quite often, it is impossible to select several lines of hidden text using the shift key with the arrow keys to extend the selection. After some variable amount of text is selected (as little as a few characters or as much as a few lines), the cursor will jump down several lines in the document. Sometimes it jumps to the end.

Is this a common or known problem?

Is there anything I can do to fix it?