add "Find in Page"

[Atn-D]

Checklist

• [x] I checked, but didn't find any duplicates (open OR closed) of this issue in the repo.
• [x] This issue contains only one feature request. I will open one issue for every feature I want to request.

What feature do you want?

Add a "find in page" button to quickly find all the places where this word is written in an article

Why do you want this feature?

I needed it to quickly find a passage in a long article, and I missed it.