x/website: Effective Go: Visible anchors for linkable sections

[Deleplace]

What is the URL of the page with the issue?

https://go.dev/doc/effective_go

Screenshot

What did you do?

I wanted to create a direct hyperlink to the section Type switch and add it to a webpage in another Go-related website.

What did you expect to see?

Feature request: all the section headings (h2, h3) would come with a trailing ¶ as a visual indicator for "Click here to get the direct URL to this section". Optionally, the ¶ char only shows up when the mouse approaches the heading. (All of this is the existing behaviour in all package pages at pkg.go.dev)

What did you see instead?

• Section headings are not hyperlinks.
• All of the h2, h3 already have an id attribute (this is great).
• All of the h2, h3 already have a corresponding link inside the Table of Contents.
• I had to search in the Table of Contents in order to click the "Type switch" and retrieve the relevant URL with the proper anchor.

[Deleplace]

This is like #50210, but milder, as all the relevant section URLs are already there, in the ToC.

[cherrymui]

cc @dmitshur