The plugin requests the result titles from core WordPress, so unless there is a custom code used of some sort, or there is a misconfiguration somewhere, then WordPress actually returned those as the titles. From the screenshot I can’t tell what types of results are those (post type, what post type, or taxonomy etc..)
Can you add temporary back-end access? I will check the configuration to see if everything is okay.
Thanks! I have logged in and checked the search preview, that seems to be okay: https://i.imgur.com/1UNnTpq.png
I could not find the search on the front-end though. I clicked a few pages, but I don’t know where it is.
This is very likely going to be a conflict caused by a 3rd party script/stylesheet, as the back-end preview is okay.
It is too generic, and applies to all header tags.
If you can’t remove or correct it, then try this additional custom CSS to override it for the search results: