I do not understand why it has no function or option to auto-highlight upon loading a page.
would be great to custom set the colors too (background and foreground).
regular expression could be another plus.

quick&simple

Fantastic add-on - just what I was looking for, something to easily check and highlight keywords in a website from a list of multiple keywords - such a time saver. And, the developer was incredibly quick and helpful about a feature request/feedback. 5 Stars!