Results not rendered when searching for sharees using email

[ishank011]

Steps to reproduce:

• Log in as Einstein, create a folder, try to share it with marie@example.org.
• In the backend, the endpoint /ocs/v2.php/apps/files_sharing/api/v1/sharees?search=marie%40example.org&itemType=folder&page=1&perPage=200&format=json still returns the correct user and a 200 status, but the results are not displayed.

My guess is that there's a prefix match with the username before displaying the users/groups, which fails for these parameters.