What exactly is the `#:~:text=` location hash in an URL? [closed]

Question

Today I noticed that some searches on Google gave me links to results with apparent instructions to highlight text.

Google brought me to What is the maximum size of a zip file on Windows 10 Pro 64... at the following url:

https://superuser.com/questions/1305867/what-is-the-maximum-size-of-a-zip-file-on-windows-10-pro-64-bit#:~:text=4%20GB%20size%20is%20a,about%2016%20exabytes%20size%20limitation

I experimented a little bit further and this seems to be a feature of Google Chrome. It highlights text on the page if you append #:~:text=something to the URL. https://example.com/#:~:text=domain seems to work fine, but only on Chrome (Chrome Beta on the left, Firefox on the right).

The word text together with different characters is a bit hard to google, so I couldn't find anything on the subject.

For finding out more information about these kinds of "URL-hacks" I want to know:
What is this feature of Google Chrome called?

Leatherneck

i can find it and others in this website chromestatus.com/feature/4733392803332096 – Piebald

I like it. I would hate it if the highlighting wouldn't go away when I scroll, but it does. – Hara

This Chrome add-on can remove those text fragments from the URL. Create a group matching all sites (.*) and inside match for (.*)#:~:.* and replace with $1. – Hara

@Makyen Would you mind to extend on why you think this question does not suit this site? I certainly think it's an edge case, however the name of the feature in question seems to be so unknown and yet needed for a technical implementation, which is what Stack Overflow can help with. – Leatherneck

@Leatherneck How is this a "a practical, answerable problem that is unique to software development"? You're literally asking "What is this feature of Google Chrome called?", which is "what's this feature of my browser called?" It could, alternately be paraphrased as "what is this portion of a URL called". Those are not programming questions. They are general technical questions. Closing this question doesn't mean it's not useful. It just means that it's not on-topic here. – Contraindicate

Answer 1

Scroll To Text Fragment

OK, with the help of a friend and at the same time via a comment from Berto99 I found it:

Apparently this is a feature called Scroll To Text Fragment. It is enabled by default since Chrome 80, but apparently not yet implemented in other browsers.

There are quite nice examples in the "W3C Community Group Draft Report". More good examples can be found on Wikipedia.

Highlighting the first appearance of a certain text

Just append #:~:text=<text> to the URL. The text search is not case-sensitive.

Example: https://example.com#:~:text=domain

Highlighting a whole section of text

You can use #:~:text=<first word>,<last word> to highlight a whole section of text.

Example: https://mcmap.net/q/108966/-what-exactly-is-the-text-location-hash-in-an-url-closed/62162093#:~:text=Apparently,Wikipedia

More advanced techniques

• Prefixing and suffixing like the example suggested in the repository for the suggestion https://en.wikipedia.org/wiki/Cat#:~:text=Claws-,Like%20almost,the%20Felidae%2C,-cats texts as proposed don't seem to work for me (yet? I use Chrome 83).
• You can style the look of the highlighted text with the CSS :target and you can opt your website out so this feature does not work with it anymore.

Leatherneck

The prefixing/suffixing does work. The example doesn't, though, because that text has not existed in Wikipedia since October 2019. This points out one of the dangers of using page content for scrolling & highlighting. – Hawkins

Throwback to Google Quick Scroll – Tazza

@Hawkins "one of the dangers of using page content for scrolling & highlighting" It's not a "danger" though, it's just a tradeoff. At worst, there would be no fine-grain positioning, that's it. Exactly as with normal #fragment links. Note: page structure can also change, rendering normal fragment positioning brittle, too. But that's fine. The fact that links break sometimes, doesn't mean they are "dangerous". It's an inherent, universal property of the web that we have to deal with anyway. – Hithermost

For anyone who came here like me wanting to know how to turn off this annoying feature, the flag in Chrome is called "Enable Text Fragment Anchor." -- chrome://flags/#enable-text-fragment-anchor – Macmacabre

@Leatherneck By the way, you can get a link to a Stack Overflow (not sure about other SE sites) comment by hovering the timestamp next to the comment. example – Ineptitude

chrome://flags/#enable-text-fragment-anchor is unavailable in Chrome 85. – Mortimer

For more details and background on this feature, see the article. – Countable

Any idea how to read this in javascript? – Burgess

Unfortunately it looks like, at this point, you can only style the element, not the highlighted text sub-part within it. So if I had an <h1> for example, I could style that via the :target, but not the text contained within, if only part of the <h1> text is highlighted by this feature. – Expiry

Since Microsoft's Edge is built on Chrome, it works in the Edge browser too. – Oestriol

Is there an equivalent feature for Firefox? – Winterwinterbottom

Wow! I've found out the equivalent feature for Safari. Check this link out, "support.apple.com/en-lb/guide/safari/ibrw40158bf7/16.0/mac/12.0" It is implemented to be constrained inside MacOS's Quick Note, saying after you create a link "A link to the webpage appears in the Quick Note, and the text in Safari is highlighted. When you revisit the website, your highlight is still there, and a thumbnail of the Quick Note appears in the lower-right corner of the screen." I think this would be very useful for those in need. – Duvall

@Winterwinterbottom No, unfortunately it is not supported for Firefox, even now. – Duvall

This is now supported in Safari on macOS, coming from Google search. Not sure exactly when this was enabled. – Limelight

Firefox could demand a sensible delimiter for multiple #key=value&pairs=to coexist in URI fragments. – Chancy

I appreciate the self-refertial example ;-) – Rugose