Facing the same issue. The workaround given in SO worked. Can someone from Chrome team acknowledge if this is indeed an issue?

Myself and several other developers at work are also experiencing the issue.

The workaround mentioned doesn't work for me (

OSX: 10.13.1 (17B48)
Chrome: 62.0.3202.94 (Official Build) (64-bit).

Blasting away my chrome profile by doing something like:

    mv ~/Library/Application\ Support/Google/Chrome/ ~/Library/Application\ Support/Google/Chrome.bak

and restarting Chrome does make the problem disappear, at least until the next time I use network throttling.

Hey Jason,
https://stackoverflow.com/questions/40143098/why-does-this-slow-network-detected-log-appear-in-chrome/46157554#46157554

Thanks for the link, unfortunately this setting also doesn't help me.

Starting with a completely blank Chrome profile, and accessing a development server on localhost, there are no console logs. If I turn on 2G throttling, and reload the page a few times, I will start seeing the console logs.

But turning off throttling does not make the logs go away.  When I still have:

- Network throttling "online"
- "#enable-webfonts-intervention-v2" set to default
- "#enable-webfonts-intervention-trigger" set to disabled

I still get the console logs, even after restarting Chrome. If I start with a fresh Chrome profile they disappear again.

It's also worth noting I get a console log for all fonts listed in the CSS, even if they are never loaded. For example if I have a woff, ttf, svg and eot, Chrome will only load the woff file, but I will receive a console log for all 4 files. I will also receive console logs for fonts which are listed in the CSS but never used, and therefore never requested by the network. 

The result is that I'm getting about 30 console logs on every page load, which is quite noisy and makes it harder to find more relevant log messages.

This issue impacts not only throttling conditions, but local source and cache reads.  I'm not aware of any conditions, in fact, where this message does NOT appear IF enable-webfonts-intervention-v2 is enabled.

To be clear, when this option is enabled, the warnings always appear, even when:

- Running from locahost
- Pulling from local cache / storage
- On extremely fast and low-latency LAN

From what I have observed, the messages appear under all conditions when enable-webfonts-intervention-v2 is enabled.

This is not a DevTools / throttling issue since closing DevTools removes throttling altogether. Over to the fonts team.

This seems like a duplicate of  Issue 764204  which was fixed in M63.

@tbansal

Version 63.0.3239.84 (Official Build) (64-bit)

"Slow network is detected. Fallback font will be used while loading: http://localhost:8080/****.woff" is still exist in console

But only one line, not ~100 lines like before

I've tried toggle offline, switch speed limit profile, etc

Some fixes were submitted against the "so many warnings" issue.

From the 63, we stop showing warnings against unused WebFonts.

Also, DevTools console starts grouping multiple similar warnings into one line. I'm not sure the exact version that starts supporting this, but definitely 65 does.

Also, from the 65, we start including a link to https://www.chromestatus.com/feature/5636954674692096 in the warning message, that could help users to solve the root problem.

And probably what you are seeing at #11 is the  issue 765378 , and tbansal@'s recent fix will mitigate it.


tbansal@, shall we merge this issue to 765378?

 Issue 765378  will fix some of the over-triggering issues that affect user experience.

I am using version 63 yet I still keep getting these warnings constantly, even for fonts served over localhost. 

63 just changed not to show warning on unused fonts.
Please track  crbug.com/765378 .