4.2.3 removed line breaks from annotations

I have a small website that reproduces ancient texts. Each word of the text is a link that, when clicked, opens a gloss on the page’s sidebar. Here is an example: http://parthiansources.com/texts/bhm/bhm-greek-text/ All of the glosses are formatted as A notes.

In the last version of WordPress, I had line breaks in the glosses so that they displayed in the sidebar like this:

βασιλεύς, έως, ὁ
(noun)
→ ‘king’

The code in the text editor to produce this was as follows:

<a class="note" alt="βασιλεύς, έως, ὁ
(noun)
→ 'king'">βασιλεύς</a>

But something changed with the update. Even though the code in the text editor looks the same, the glosses now display without line breaks and look like this:

βασιλεύς, έως, ὁ (noun) → ‘king’

I cannot add <br> or <p> tags within the A notes in the text editor; this messes something up and causes the word to not display at all.

Would be profoundly grateful for any help! And particularly for a solution that wouldn’t require me to recode hundreds of individual words.