📝 Issue Description

It looks like there may be some issues when copying headings when using either double click (select a word) or triple click (select a paragraph/logical unit). The behavior seems to be different depending on the browser and be related to heading anchor links.

Chrome

When the viewport width is less than 95em (the heading anchor link is at the end of the heading) and double clicking and copying a heading with a single word or the last word of a multiple words heading will inject Section in the clipboard text (I am assuming this is the first word of the heading anchor link screen reader text).

For example, going to this page and double clicking and copying the heading Features will copy FeaturesSection instead of Features. Double clicking and copying the word Principles in the heading Design Principles will copy PrinciplesSection instead of Principles.

Triple clicking is working as expected.

Firefox

When the viewport width is less than 95em (the heading anchor link is at the end of the heading) and triple clicking a heading and copying will inject the entire heading anchor link screen reader text in the clipboard text.

For example, going to this page and triple clicking and copying the heading Features will copy FeaturesSection titled Features instead of Features.

Safari

When the viewport width is less than 95em, double clicking or triple clicking a heading with a single word or the last word of a multiple words heading will visually select the entire page and copying will inject Section in the clipboard text too.

When the viewport width is greater than 95em, triple clicking a heading with a single word or the last word of a multiple words heading will visually select the entire page (the clipboard content is fine in this case).

📋 On which page(s) it occurs

I used https://docs.astro.build/en/concepts/why-astro/#features as an example but this can repro on every pages with headings.

🤔 Expected Behavior

The selection should visually match what is expected (either a word or an entire heading but never the entire page) and the copied text should match such selection and never contains invisible text.

👀 Current Behavior

The selection can be visually wrong and the copied text can include invisible text.

🖥️ Browser

Chrome 125.0.6422.4 - Firefox 125.0.2 - Safari 17.4.1

📄 Additional Information

No response