Clacks Overhead - GNU Terry Pratchett

How to install an extension Open in Chrome Web Store

CRX ID

lnndfmobdoobjfcalkmfojmanbeoegab

Status

Extension status: Featured
Live on Store

Description from extension meta

GNU Terry Pratchett. Show user when 'Clacks-Overhead' appears in HTTP headers.

Image from store

Description from store

This extension is a tribute to the late Terry Pratchett (https://en.wikipedia.org/wiki/Terry_Pratchett). It displays an icon when the user visits a website sending a "Clacks Overhead" message. If the user clicks on the icon, it will display the message and animated clacks semaphore code.

More information can be found here: http://www.gnuterrypratchett.com/

Notes:
1. This extension does not collect any data or send any information anywhere.
2. All code is open source on Github: https://github.com/newfolder0/chrome-clacks

Contributors:
- Peter Bell (original author)
- Charlie Wheeler-Robinson (bug hunting, refactoring, improving in early versions)
- Jimmy Nyström (code)
- Melanie Wilberforce (icons)
- Rob Grundy (who made the Firefox extension) for sending me the clacks icons used in the animation
- Backspindle Games for producing the clacks icons in the animation
- Sap1ens, jwakely, and Amy Atha-Nicholls (generously offering new icons)
- yousuf811 on Github (squashing bugs)
- Jarek Glowacki for some CSS help
- Jake Heimark (hmk on GitHub) for fixing the manifest and keeping this extension alive in 2024
-See GitHub issues and pull requests for others

Latest reviews

Oliver Warlow 2025-09-06: Finding sites that you wouldn't expect to do it that do it so so delightful. When you do a Google search and one of the results that preview content is loaded from does it you get a little minigame of 'which search result has the headers'
Jóhannes Birgir Jensson 2025-07-14: Does not read correctly from some websites that do have a X-Clacks-Overhead, which another, now discontinued extension, did display correctly
Wild Calendar 2025-04-08: Nice visibility of the icon but the detection of clacks messages only seems to work on most sites with the message.
Chris Carter 2024-10-31: A fun little surprise to find random sites with the Clacks headers now and then.
Nikil Sankar 2024-09-28: This is why I love internet. Sir Terry is not death till the Discworld community is breathing.
James Longman 2024-09-14: Nothing less than what the internet should be used for.
Tom Trval 2024-01-04: Just perfect. And thank you for fixes :)
Daniel Colburn Smith 2023-02-24: Thanks so much for fixing this! Works wonderfully.
Daniel Colburn Smith 2023-02-24: Thanks so much for fixing this! Works wonderfully.
David Pohan 2022-06-29: The extension works as expected. It's nice to remember. ❤
David Pohan 2022-06-29: The extension works as expected. It's nice to remember. ❤
Michael Campbell 2022-03-02: Seems to be working for me. Most sites don't have it but I tested it by going to Discworld Emporium and it lit up as expected. A shame it doesn't light up on this page, but I blame Google, not the developer.
Michael Campbell 2022-03-02: Seems to be working for me. Most sites don't have it but I tested it by going to Discworld Emporium and it lit up as expected. A shame it doesn't light up on this page, but I blame Google, not the developer.
Rebecca 2021-04-14: It broke down a while ago and no longer works. Maybe an update is needed?
Rebecca 2021-04-14: It broke down a while ago and no longer works. Maybe an update is needed?
Caroline Erickson 2020-06-25: love this, thank you. a man is not dead while his name is still spoken.
Caroline Erickson 2020-06-25: love this, thank you. a man is not dead while his name is still spoken.
Katarzyna Jędrzejek 2020-03-12: It's been 5 years today. I've never stopped using this extension and it still brightens my day when I'm able to spot incoming clacks signal. GNU Terry Pratchett
Katarzyna Jędrzejek 2020-03-12: It's been 5 years today. I've never stopped using this extension and it still brightens my day when I'm able to spot incoming clacks signal. GNU Terry Pratchett
Shonaigh Douglas 2019-05-22: It used to be cool, seeing the little icon light up on some websites. Sadly, it no longer seems to work - it doesn't appear in the address bar anymore and the control icon is always lit up. I know there are a lot of Discworld fans, but not that many!
Shonaigh Douglas 2019-05-22: It used to be cool, seeing the little icon light up on some websites. Sadly, it no longer seems to work - it doesn't appear in the address bar anymore and the control icon is always lit up. I know there are a lot of Discworld fans, but not that many!
Jan Goyvaerts 2019-03-07: Is it working properly ? I've got the lantern burning for all sites I visit now.
Jan Goyvaerts 2019-03-07: Is it working properly ? I've got the lantern burning for all sites I visit now.
Daniel Colburn Smith 2019-01-09: Sadly this has stopped working.
Daniel Colburn Smith 2019-01-09: Sadly this has stopped working.
RC 2018-12-27: In the most current version of Chrome ever site, except (humorously) the chrome web store, shows as sending the clacks header. This appears to be broken in Chrome 71. <3
RC 2018-12-27: In the most current version of Chrome ever site, except (humorously) the chrome web store, shows as sending the clacks header. This appears to be broken in Chrome 71. <3
Marko Koivuniemi 2018-07-25: Excellent tribute to excellent writer. Terry Pratchett deserves this.
Marko Koivuniemi 2018-07-25: Excellent tribute to excellent writer. Terry Pratchett deserves this.
Ghoul Cubes 2018-06-12: "It is said that your life flashes before your eyes just before you die. That is true, it’s called Life"
Ghoul Cubes 2018-06-12: "It is said that your life flashes before your eyes just before you die. That is true, it’s called Life"
Dave Gumble 2018-03-26: shows you aint dead.
Dave Gumble 2018-03-26: shows you aint dead.
K Kreutzer 2017-11-25: It's always a moment of joy when my clacks lights up on a page I never expected it to. #GNUTerryPratchett
K Kreutzer 2017-11-25: It's always a moment of joy when my clacks lights up on a page I never expected it to. #GNUTerryPratchett
Jenni Warren 2017-01-04: I ATE'NT DEAD
Jenni Warren 2017-01-04: I ATE'NT DEAD
Paul J 2016-12-10: A man is not dead while his name is still spoken
Paul J 2016-12-10: A man is not dead while his name is still spoken
FM S (snapsi) 2016-10-13: absolute must have... really! Thanks for everything Terry.
FM S (snapsi) 2016-10-13: absolute must have... really! Thanks for everything Terry.
Amanda Maree Grant 2016-09-19: never forgotten
Amanda Maree Grant 2016-09-19: never forgotten
Michael Koorey 2016-07-19: An excellent tribute to an amazing author.
Michael Koorey 2016-07-19: An excellent tribute to an amazing author.
Chris Stephens 2016-06-09: Perfect!
Chris Stephens 2016-06-09: Perfect!
Najwa Laylah 2016-05-13: The only browser extension that can make me cry.
Najwa Laylah 2016-05-13: The only browser extension that can make me cry.
Angie Chick 2016-03-02: I love seeing this pop up on sites that I wouldn't have expected to find it. He may be gone from us, but his name will live on forever !

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