I might not be looking in the right place, but before a recent upgrade I could do a remote IMAP search by using search then clicking send query to server or something. That functionality seems to be missing in newest version, or has it moved?
The feature is still there on the search results page. The icon is a magnifying glass with a cloud in it.
Remote search has to be enabled under Settings > [Account] > Search > Enable server search.
The functionality is only available when searching a single folder. So you won’t be able to perform a remote search from e.g. the Unified Inbox.
Thanks. This was my issue (the unified inbox)