I would also like to add that the official documentation page (https://www.chromestatus.com/feature/5636954674692096) of this feature states:

"Web site owners can opt-out from the intervention by setting CSS font-display to other than 'auto'."

Our font-display property is set to `swap` or `optional`, yet we still keep seeing these errors.

I am going to change the message level from "error" to "warning". The message should not show up when using `swap` or `optional`. cc'ing toyoshim@ and ksakamoto@ for that.

Adam, do you see this error when you are using network throttling on devtools, or do you see it at all times?

Thanks, we see it all the time. We don't use network throttling at all.
We use `font-display` to try to avoid them, but the warnings still show up.

Warnings also show up for 3rd party plugins that use web fonts, which we have no control over though. These warnings can't be filtered out in the console, and area really distracting and cumbersome.

That's bad.

I can confirm in the latest Chrome version (M71), these message show up at Info level. So, that problem is already fixed.

We still need to figure out why these are showing up for non-auto fonts, and on fast connections.

Also, I suspect there's still something wrong with the actual algorithms detecting a slow network, as we often get these messages on our gigabit internet connection.

It could be that the CDN or site the fonts are loaded from is slow, but in that case the warning text is misleading, because your own network connection is fine.

Great to hear it's at least back to info, but too bad we have to wait 3 versions until this is fixed.

Right, the algorithm tries to differentiate between network being slow and server being slow (e.g., in case of hanging GETs, long polling requests, XHRs). However, sometimes it gives false positives. We are looking at ways to improve the accuracy.  Issue 823322  and  Issue  834119  track the work.

You can start Chrome with command line switch --force-effective-connection-type=4G to disable this. Alternatively, in chrome://flags/, set the dropdown in "Override effective connection type" to 4G.

Looks like root cause is already identified in C#8, hence removing the needs-bisect label. Please feel free to add it back if this needs a bisect.

Thank you!

It's very curious. In our source code, the message level has been info-level over a year. On my Chromebook on 69.0.3497.35, I also confirm that it's still info-level message.

Adam, do you still see this error level message even on the latest 69 stable?

Also, "Group similar" function in the console worked for these messages, but it may not be able to group recently? I'm not familiar with how the console detect similar messages though.

Even without "group similar" disabled, the messages still showed up as errors. After updating to Chrome 69, I am not seeing the messages at all at the moment. But it could be they are not triggering because network speed is faster this morning. I will keep an eye on it throughout the day and report back.

Looks like the root problem (i.e. the message is shown at the error level) is fixed and updating to Chrome 69 would have fixed it?  I'm tentatively closing this.

Adam- if you still see the problem after Chrome 69 feel free to reopen, or file a new one if the network detection needs to be improved further. Thanks for reporting & helpful feedback!