Thank you for the details, it helped me a lot.
I have found multiple issues, unfortunately only one was partially related to ajax search pro.
1. The jquery script was missing from the header on some admin pages. I'm not sure what's causing it, it's probably a cache or minification related plugin. Anyways, I have found a workaround by editing the search plugin back-end code. I will probably implement a similar solution to the upcoming version, as I think this can be avoided.
2. After some investigation I have found that the ClickMeter Link Shortener and Analytics plugin script is loaded on each and every back-end page of the website – which I think it shouldn't be. Mostly because there is a line of code, which finds the element with the ID of “content” and removes all the HTML tags from it's content. That's what causes the issue, as the search options are contained within an element of which the ID is “content”. I recommend disabling that plugin until you configure the search, it will solve the problem.Best,
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