When you go to the the search box in Gerrit (top right) with Firefox, enter "status:merged owner:aklapp" and hit RET twice, the result page https://gerrit.wikimedia.org/r/#/q/status:merged+owner:%22Aklapper+%253Caklapper%2540wikimedia.org%253E%22,n,z is correctly displayed, but with an overlay error message of:
Code Review - Error
User Aklapper %3Caklapper%40wikimedia.org%3E not found
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Clicking on [Continue] will enable you to use the result page as normal.