The font size on the inline query editor (when syntax highlighting is on) is way too big. Only 3 lines of a query can fit in the box at once.
The problem is the .CodeMirror class, it sets the size to 140%. That property should just be removed entirely.
Can you show a screenshot? I can't reproduce the problem on QA_3_5 branch.
This bug was fixed in repository and will be part of a future release; thanks for reporting.