1. Unfortunately the highlight only works within the ajax results list. The problem is that after clicking on the result link, it is not possible to tell if it comes from the search plugin, or from another part of the website – therefore if it was possible, it would still highlight everything regardless if it came from the search plugin or not.
2. Yes. On the Layout Options -> Results Behavior panel: https://i.imgur.com/6NfsxzJ.png
3. Yes, it can be without changing the theme code if your theme supports it. On the Ajax Search Pro menu you can choose which instance you want to replace the default search: https://i.imgur.com/NGjlXWe.pngBest,
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