[docs] Link h2 and h3 in docs

[mj12albert]

Example: https://deploy-preview-1795--base-ui.netlify.app/react/components/checkbox#api-reference

Closes #1181

• I have followed (at least) the PR section of the contributing guide.

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[mj12albert]

@colmtuite I just used a material icon here, maybe you have a better one? (not sure where the existing ones are from)

[atomiks]

Think the icon should be revealed on focus as well

[colmtuite]

@mj12albert

• remove the icon
• Do text-decoration-color: currentColor
• Do text-underline-offset: 4px;

[mj12albert]

• remove the icon
• Do text-decoration-color: currentColor
• Do text-underline-offset: 4px;

Updated! @colmtuite

[colmtuite]

@mj12albert We need responsive scroll-margin-top now, because the mobile header is 48px, but scroll-margin is just 24px. So gotta set it for mobile-first, then tweak it back to 24px for larger screens.

[oliviertassinari]

In the execution, could we also bring this from Material UI mui/material-ui#41994? I frequently select the header text and using a <a> break this flow.

[colmtuite]

@oliviertassinari Wouldn't that break native functionality of dragging an <a> into the browser search bar? What's the use case for selecting a range inside a heading?

[oliviertassinari]

Wouldn't that break native functionality of dragging an into the browser search bar?

@colmtuite It does (I never use this). If we can only have the ability to double-click to select the whole text, it would help, but I have a workaround (selecting text, starting outside of the element, so it's kind of ok).

What's the use case for selecting a range inside a heading?

I think the use case is maintainer-related, not about end-users. I usually use this to leave comments on the heading structure, propose changes.

[mj12albert]

Updated scroll-margin-top: https://deploy-preview-1795--base-ui.netlify.app/react/components/checkbox#api-reference @colmtuite

[colmtuite]

@mj12albert On mobile now when I click a heading, it's touching the header/appbar.

[mj12albert]

@mj12albert On mobile now when I click a heading, it's touching the header/appbar.

@colmtuite Fixed: https://deploy-preview-1795--base-ui.netlify.app/react/components/checkbox#api-reference