Search result highlight changes color over time

Created by: rvantonder

• Sourcegraph version: master (v3.9.4+)
• Platform information: Tested on Chrome and Safari

Perhaps some duplicate highlighting.

Steps to reproduce:

1. Visit this search query
2. See result highlights changing color and get progressively brighter.

Expected behavior:

Highlight color stays the same.

Actual behavior:

Highlight color gets brighter.