The 'Browse by category' box you see on the top of the page is known as the category quick filter. This filter allows reviewers to quickly view applications from a selected category and is available on all reviewing modes, including galleries.
By default, the 'Browse by category' option is visible to reviewers, however, you may wish to hide the category quick filter (particularly if you don't have many categories).
To hide the filter:
From the Manage workspace, go to Reviewing > Settings > Score sets
Click on the name of the score set you where you want to hind the category quick filter
Go to the 'Display' tab
Under 'Application list', untick Category quick filter
Click Save
Note: removing the quick filter for reviewers will also hide it from the leaderboard. However, the standard 'Advanced' search filters will remain.
