Currently, the anchors are revealed when the user mouses over the full-width horizontal strip occupied by the section header. This is problematic for two reasons:

1. The full-width trigger area causes anchor links to flash as the user scrolls down the page.
2. The height of the trigger area is very small, so the anchor would disappear and reappear in rapid succession as the user mouses in and out of it, including when they are moving their mouse towards it to click on it.

An alternative to reduce the flashing is to reduce the trigger area to just the header text (rather than the full width), as done in https://gerrit.wikimedia.org/r/#/c/191845/, but this makes the anchor links much less discoverable.

Other approaches to consider:

• Introduce a delay before showing (and hiding?) the anchor links
• Somehow increase the height of the trigger area
• ...

See also
https://fr.wikipedia.org/wiki/MediaWiki:Gadget-AncreTitres.js
which provides internal links in wiki syntax (very convenient! :-)

Change 192458 had a related patch set uploaded (by Wctaiwan):
Add a small delay to anchor link trigger

https://gerrit.wikimedia.org/r/192458

Patch-For-Review