I've actually found a bug in the code, that's why it showed the product from the wrong category. It was a very rare bug, that's why I didn't know about it. Thank you for the ftp details, it helps me to discover such bugs. I'm adding this to the next bugfix version.
I have also made a few tweaks:
– I have switched the image handler to BFI thumb on the Compatibility Settings submenu – it's faster a bit than the other one
– I have disabled the Search in Terms option. The performance went up from 2 seconds to 0.09 seconds!! It's very performance consuming if you have lot's of products 😉 It also gives more accurate results if disabled. You can of course switch it back if you want to. (General Options->Sources, bottom of the page)
About the “fender combo” search term. Currently I get the following results: https://i.imgur.com/mwxGNp6.png
There is one odd result, the Vox amPlug, but it's there because it's content contains both the “fender” and “combo” words: https://i.imgur.com/XjSV9lE.png
You can try to use the “AND with exact keyword mathces” for keyword logic, it will show more strict results – but be aware that partial results then will not appear.
Everything else looks all right.Best,
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