Hi,
I recommend using the option, where you need to input the least values – their performance is equivalent. If you have more things to exclude than to include, then use the inclusion istead, and vice versa.
However I don’t recommend including or excluding too many items, it can decrease the performance greatly. These options are to refine the search by bits.
The term issue is interesting, as some terms are printed correctly some are not. I’ve looked up the code in that section on my local server, it uses the get_term() internal WordPress function to display the terms after saving – for some reason it returns an error or a non-existent term in your case, so it’s not visible after saving. Feel free to add temporary FTP access and I will look at that section of the code on why that is failing.
Best,Ernest Marcinko
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