Results disappear when filters are used

The quiz results page has a table with the following special filters:

- only show users best result
- do not show quizzes in progress

Selecting these filters can make all the results in the table disappear, even when the filters shouldn't hide the quiz results.

The top of the table has options to filter by Username, Time Started, Time Finished, Score, Evaluated.

If I change the filter for the Start time, all the results disappear.