If a question bank with a large number of pages is used the questions in the question bank don't resize when the browser window is resized. In the example I have there are 14 pages of questions in the selected category. I found the MDL-45611 that was similar but not the same as this issue. https://tracker.moodle.org/browse/MDL-45611?jql=text%20~%20%22question%20bank%20page%22
The top of the question bank block adjusts as expected. If I switch to a category without a large number of pages the questions adjust to the size of the window as expected.