See if it's fixed in Chrome Canary, in which case it'd be  bug 843250 .

Still reproducible in both Chromium and Canary (69 both)

koskokos@ Thanks for the issue.

Tested this issue on MacBook Pro 10.13.3 High Sierra by connecting to a external display on the reported version 67.0.3396.99 and the latest Canary 69.0.3496.0 and unable to reproduce the issue by following the below steps.

1. Connected MacBook pro to external display and launched chrome.
2. Added the extension 'Tampermonkey' and clicked on the extension icon. Cannot observe any blurry text.
3. Dragged Chrome window to the external display and cannot observe any blurry text there as well.
Attached is the screen shots for reference.

Request you to check the issue on a new chrome profile without any flags/extensions and update the thread with the observations.

Thanks..

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Thanks for response. I tried new profile and also tried in Canary once more and I still can see the problem that it draws lo-dpi extension UI (any extension) over hi-dpi other parts of Chrome UI. I'm attaching screenshots as well.

"Dragged Chrome window to the external display and cannot observe any blurry text there as well" - that cannot be the case as "blurry" is lo-dpi, so it won't be possible to see that on lo-dpi external display (as everything there will be "blurry" relatively to hi-dpi Macbook).

I don't know if it can matter but my Macbook is late 2013 version.
Also I just tested on Chromium 66 as I stated it worked in previous version and still can it is working there, attaching screenshot as well.

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Thank you for providing more feedback. Adding the requester to the cc list.

For more details visit https://www.chromium.org/issue-tracking/autotriage - Your friendly Sheriffbot

Unable to reproduce the issue on mac 10.13.3 MacBook Pro (Retina, 15-inch, Mid 2015) using chrome reported version #67.0.3396.99.

Observed that all UI is drawn in hi-res when an external display is connected to hi-dpi Macbook.
As the issue is not reproducible from TE-end. Hence, removing Needs-Bisect label and requesting Platform>Extensions team to please have a look into the issue.

Thanks...!!

As per comment #4 and #7, as the issue is not reproducible at TE end, adding 'TE-NeedsTriageHelp' label and requesting the appropriate team to look into the issue and help in further triaging.

Thanks..