I have noticed that many times that the TOC will "shift down" out of view, when clicking on a topic. The most recent was clicking on "Feast" in the Zondervan Enc. of the Bible.
But this behavior only seems to happen sporadically, and in the following circumstances (at least this is what happened within ZEB, D-G):
- You must click on a topic with an arrow (expanding arrow). In this case, clicking to the left of "Feast"

2. And you must click on the "arrow." Clicking on the word will not reproduce this bug.
Doing so makes the topic one has selected drop below the range of view. This behavior keeps happening as you click on the arrow.
Note: it does not happen on every word with an arrow. In this case, the first few "F" topics with an arrow worked fine. But by the third or fourth arrow, and I believer for all the rest of the "arrows", this bug was consistently observed.