[REG 3.3 -> 3.4] Plugins can't be sorted by Vendor

1. Open the "Installed Plugins" dialog using "Help" -> "About Plugins...".
2. Click on the headline of the "Vendor" column.
   A small arrow appears in the headline. Nothing else happens.

After clicking the headline, plugins should be sorted by their vendor. This used to work in Creator 3.3.