Yep, adding new, usable filters is actually extremely difficult from the developer (my) side. The recently implemented post tag filter took me over 60 hours alone with all the logics and testing, until everything worked fine. It appears to be really easy because of the interface, but in reality there are hundreds of things to take care of.
I highly doubt that would work to be honest with you. If there was any easy temporary solution to this, I would do it for you. I don't like to disappoint anyone, I usually make modifications if needed, but in this case I can't do anything, it's too difficult to implement it quickly, I'm sorry.Best,
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