Highlight search term occurence on page

[strogonoff]

This may be best implemented after search overhaul.

Currently, clicking a search result takes the reader to the corresponding subresource. However, when multiple subresources contain the search term, it might be beneficial to highlight (in a more subtle way) other occurrences of the term on the page.

Caveat: search logic does stemming & other manipulation of the query, so a naive approach of highlighting the exact match could create an unwelcome discrepancy. Workarounds could be: 1) using Lunr somehow to report the location of the term (see more: link TBD), 2) TBD.

Highlighting:

• https://developer.mozilla.org/en-US/docs/Web/API/CSS_Custom_Highlight_API
• To update when displayed resources change: possibly https://stackoverflow.com/questions/20420577/detect-added-element-to-dom-with-mutation-observer