JabRef 4.2-dev--snapshot--2018-03-09--master--988fb54a9
Windows 8.1 6.3 x86
Java 1.8.0_161

1. Multi-line PDF annotations like these:

are shown with "line breaks" like this.

2. There is currently a wide white space between the annotation text and the date/page number. Text should be warped with the maximum available/appropriate width.

3. Then, the height of each annotation item should be "auto".

4. I suggest the font size of the extracted annotations in the left-hand panel be reduced (e.g., x0.6). The right hand panel font size looks OK.