Items not searchable by guest accounts after applying a sensitiviy label

We have enabled the integration of sensitivity labels for SharePoint Online and OneDrive in our tenant. We now noticed that items that get assigned to a sensitivity label that uses encryption are not searchable anymore by guest users. The guest accounts have access to the item and also have access to open the encrypted item.

As soon as such a label is set, the items disappear from SharePoint search for any of our guest user accounts.