Bret, have you noticed 404 errors sometimes when going back in navigation links?
http://blittle.github.io/basics/README.html
When navigating back to already visited link and then again forward, most probably between top level nodes only like here between Introduction and Basics:

Let me know if you are able to recreate this, I could help with fixing it.
Browser: Chrome obviously
Thanks!

Hi,

I didn't find info about blackboxing feature. Probably it has been updated in the chrome dev tools.

Need a roadmap for updating the book for newer chrome features.

I just wanted to learn about Websockets (from an on-the-wire network view), but it seems the combination of the code at https://blittle.github.io/chrome-dev-tools/network/websockets.html and my Chrome (on Windows Version 90.0.4430.93 (Official Build) (64-bit) ) is causing errors as below and attached. I presuming the API changes are the most relevant.

Error with Permissions-Policy header: Unrecognized feature: 'interest-cohort'.
websockets.html:2 [Deprecation] Application Cache API manifest selection is deprecated and will be removed in M85, around August 2020. See https://www.chromestatus.com/features/6192449487634432 for more details.
websockets.html:1 Creating Application Cache with manifest https://blittle.github.io/chrome-dev-tools/manifest.appcache
websockets.html:1 Application Cache Checking event
websockets.html:1 Application Cache Error event: Invalid or missing manifest origin trial token: https://blittle.github.io/chrome-dev-tools/manifest.appcache
websockets.js:17 Mixed Content: The page at 'https://blittle.github.io/chrome-dev-tools/network/websockets.html' was loaded over HTTPS, but attempted to connect to the insecure WebSocket endpoint 'ws://echo.websocket.org/'. This request has been blocked; this endpoint must be available over WSS.
testWebSocket @ websockets.js:17
init @ websockets.js:13
(anonymous) @ websockets.js:63
(anonymous) @ websockets.js:64
websockets.js:17 Uncaught DOMException: Failed to construct 'WebSocket': An insecure WebSocket connection may not be initiated from a page loaded over HTTPS.
at testWebSocket (https://blittle.github.io/chrome-dev-tools/network/websockets.js:17:15)
at init (https://blittle.github.io/chrome-dev-tools/network/websockets.js:13:3)
at https://blittle.github.io/chrome-dev-tools/network/websockets.js:63:2
at https://blittle.github.io/chrome-dev-tools/network/websockets.js:64:2
testWebSocket @ websockets.js:17
init @ websockets.js:13
(anonymous) @ websockets.js:63
(anonymous) @ websockets.js:64
websockets.html:1 Mixed Content: The page at 'https://blittle.github.io/chrome-dev-tools/network/websockets.html' was loaded over HTTPS, but requested an insecure script 'http://cdn.mathjax.org/mathjax/2.0-latest/MathJax.js?config=TeX-AMS-MML_HTMLorMML'. This request has been blocked; the content must be served over HTTPS.
plugin.js:2 Uncaught ReferenceError: MathJax is not defined
at plugin.js:2
at Object.execCb (app.js:1)
at n.check (app.js:1)
at n.enable (app.js:1)
at n.init (app.js:1)
at app.js:1
(anonymous) @ plugin.js:2
execCb @ app.js:1
check @ app.js:1
enable @ app.js:1
init @ app.js:1
(anonymous) @ app.js:1
setTimeout (async)
req.nextTick @ app.js:1
s @ app.js:1
requirejs @ app.js:1
(anonymous) @ plugin.js:1
websockets.js:54 Uncaught ReferenceError: websocket is not defined
at doSend (websockets.js:54)
at HTMLButtonElement.document.getElementById.onclick (websockets.js:7)
doSend @ websockets.js:54
document.getElementById.onclick @ websockets.js:7

Hi Bret,

Love your "Down and Dirty with Chrome Dev Tools", really learned from it!

I see you already made a issue where you say you should update this on newer versions. But still I would like to give my 2 cents.

Ik have the following setting:

• UserAgent:
  • Mozilla/5.0 (Macintosh; Intel Mac OS X 10_10_4) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/44.0.2403.155 Safari/537.36

When walking though the topics I had the below comments/suggestions/experience:

• http://blittle.github.io/chrome-dev-tools/sources/skip-frameworks.html
  • option not available any more in "experiments"
• http://blittle.github.io/chrome-dev-tools/sources/web-workers.html
  • don't see the workers option in my Chrome web-inspector/sources. Where can I find them/enable them.
• http://blittle.github.io/chrome-dev-tools/sources/maps.html
  • this option seems to be not available any more. Think it's default now, it works as you say it does.
• http://blittle.github.io/chrome-dev-tools/timeline/README.html
  • example explanation, didn't know what todo on this question + answer
• http://blittle.github.io/chrome-dev-tools/profiles/README.html
  -example explanation, didn't know what todo on this question + answer
• http://blittle.github.io/chrome-dev-tools/console/README.html
  • example explanation, didn't know what todo on this question + answer
• http://blittle.github.io/chrome-dev-tools/console/monitor-events.html
  • doesn't work out of the box when doing "monitorEvents($x('//*[@id="section-gitbook_10"]/textarea'), ["scroll"]);" for example. Also the "monitorEvents(window, ["scroll"]);" doesn't work on this page. Other pages it does, so probably the setting on this project doesn't work (css with divs or something?).

Regards,
Derk

@blittle Great work on writing this very useful book 👍

I was wondering if you would be willing to update to a newer version of GitBook, which has many fixes and improvements as well as radically different & better default theme (check http://gitbookio.github.io/javascript/).

Simply update gitbook through npm, rebuild and push to gh-pages.

We like your book a lot, so it's one of the books we've chosen to feature on the new version of gitbook.io (coming out later today).

The book is available at https://blittle.github.io/chrome-dev-tools

Would be great if you added it to the repository description. Something like this: