I just tried the search again on the front-end and it's working as normal. I'm getting results within 1-2 seconds.
The back-end preview is not responding, but it might be related to the fact that it also sends some extra data back to the server.
If you don't mind, I would rather not start playing around debugging that, since it's not the same as the one on the front-end. As long as the front-end is working correctly, there is nothing to worry about.
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