Able to reproduce the issue on reported version 67.0.3378.0 using Windows-10, hence providing Bisect Info
Note: Issue is not seen on Mac 10.12.6, Ubuntu 14.04.
Bisect Info:
================
Good build: 67.0.3372.0
Bad build: 67.0.3373.0

You are probably looking for a change made after 543782 (known good), but no later than 543796 (first known bad).

https://chromium.googlesource.com/chromium/src/+log/dd80e340ad44a8e8c9214b6449fe79e028571623..d4032b171ce2c4de0b2c2fdfbecdc9649708d08b
Suspecting: https://chromium.googlesource.com/chromium/src/+/a6de7e84dde8bd13f511bb5c09acb5a0eb8a747a

Change-Id: I04466aab7e978ad51e5e579488e29789cda9ab72
Reviewed-on: https://chromium-review.googlesource.com/961552

@Tommy C. Li: Please confirm the issue and help in re-assigning if it is not related to your change.
Adding ReleaseBlock-Stable as it is seems a receent break, feel free to remove it if not applicable.

Thanks!

 Issue 823123  has been merged into this issue.

M67 Stable promotion is coming soon. Your bug is labelled as Stable ReleaseBlock, pls make sure to land the fix and request a merge into the release branch ASAP. Thank you.

*** Bulk Edit ***
M67 Stable promotion is coming soon. Your bug is labelled as Stable ReleaseBlock, pls make sure to land the fix and request a merge into the release branch ASAP. 

If fix is already merged to M67 and nothing else is pending, pls mark the bug as fixed. Thank you.

*** Bulk Edit ***
M67 Stable promotion is coming VERY soon. Your bug is labelled as Stable ReleaseBlock, pls make sure to land the fix and request a merge into the release branch ASAP. 

If fix is already merged to M67 and nothing else is pending, pls mark the bug as fixed. Thank you.

Hey, I actually cannot reproduce this on Chrome Canary Windows with the Dark Reader extension (same as in the test case).

Can you try reproducing again? Especially try deleting your user profile directory, as it kind of looks like the extension popup may be zoomed in for some reason...

https://chromium.googlesource.com/chromium/src/+/master/docs/user_data_dir.md#Windows

Tommy

This is what I got when I tested just now by the way.

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Removed the user profile, updated video drivers: still happens. Not only for Dark Reader, but for other extensions too, e.g. AdBlock.

Zooming also works without blur in stable Chrome (to do this click Dev Tools button at bottom, it will open new window, then press Ctrl +).

Chrome 68.0.3425.0

Video info:

Intel(R) HD Graphics 4600
2016-11-10
20.19.15.4549

NVIDIA GeForce GT 750M
2018-05-07
24.21.13.9764

See the side by side comparison in attachment

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This is easily reproducible with any extension in Windows 7 + nVidia 750 Ti. Simply set OS scaling in Windows display control panel to 150%. The bug is definitely real and still present in Canary so there's no way to dismiss it as WontFix. I also confirm the per-snapshot bisect range in #c2, but it'd be nice if TE does a per-revision bisect.

#c9 > as it kind of looks like the extension popup may be zoomed in for some reason...

The bug report is about "DPI>100%" (see the title) meaning DPI larger than 100%, so you need to set the DPI in your OS:
https://www.google.com/search?q=set+windows+dpi

 Issue 842459  has been merged into this issue.

Found a workaround:
Disabling chrome://flags/#secondary-ui-md helps

I can confirm that the culprit CL indeed is causing extension popups to look blurry at >100% DPI on Windows.

I'll submit a fix shortly.

This is reproducible on Linux HiDPI as well, so I expect any Aura platform using layer masks at High DPI blurs text.

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Here's a stopgap patch that will prevent us from shipping the regression to users: https://chromium-review.googlesource.com/c/chromium/src/+/1057966

But it's not a root-cause fix.

+cc jdonnelly

Omnibox Popup in Material Refresh is going to look blurry on HiDPI until we fix the root cause of this bug.

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/13549a45248294edd44aaac6000ffd74887e1e94

commit 13549a45248294edd44aaac6000ffd74887e1e94
Author: Tommy Li <tommycli@chromium.org>
Date: Mon May 14 23:27:16 2018

Revert "Views: Turn on InkDropMasks for Windows."

This reverts commit a6de7e84dde8bd13f511bb5c09acb5a0eb8a747a.

Reason for revert: Makes extension popups blurry with non-integral
scale factors.

Bug:  824963 

Original change's description:
> Views: Turn on InkDropMasks for Windows.
>
> It seems to "just work".
>
> Tested on:
>  - Windows 10
>  - Windows 10 with --disable-gpu
>  - Windows 7
>  - Windows 7 Classic mode (Aero disabled)
>
> Bug: 713359
> Change-Id: I04466aab7e978ad51e5e579488e29789cda9ab72
> Reviewed-on: https://chromium-review.googlesource.com/961552
> Commit-Queue: Tommy Li <tommycli@chromium.org>
> Reviewed-by: Mohsen Izadi <mohsen@chromium.org>
> Reviewed-by: Trent Apted <tapted@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#543785}

TBR=tapted@chromium.org,mohsen@chromium.org,tommycli@chromium.org

# Not skipping CQ checks because original CL landed > 1 day ago.

Bug: 713359
Change-Id: I854e2315e5cd73c7aca67f0d7d226cb67102ff32
Reviewed-on: https://chromium-review.googlesource.com/1058289
Commit-Queue: Trent Apted <tapted@chromium.org>
Reviewed-by: Tommy Li <tommycli@chromium.org>
Reviewed-by: Trent Apted <tapted@chromium.org>
Cr-Commit-Position: refs/heads/master@{#558526}
[modify] https://crrev.com/13549a45248294edd44aaac6000ffd74887e1e94/ui/views/animation/ink_drop_host_view.cc
[modify] https://crrev.com/13549a45248294edd44aaac6000ffd74887e1e94/ui/views/controls/native/native_view_host_aura.cc

Pls update the bug with canary result tomorrow. 

This bug requires manual review: We are only 13 days from stable.
Please contact the milestone owner if you have questions.
Owners: cmasso@(Android), cmasso@(iOS), kbleicher@(ChromeOS), govind@(Desktop)

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

Able to reproduce the issue on chrome version 67.0.3378.0.
Verified the fix on Ubuntu 14.04 using Chrome version #68.0.3431.0 as per the comment #0.
Attaching screenshot for reference.
Observed that "Text, images, borders have sharp edges"
Hence, the fix is working as expected. 

Note: Unable to verify the fix on Windows 32 & 64 due to issue: 843012.

Thanks...!!

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The NextAction date has arrived: 2018-05-15

This did not make today's Windows Canary (68.0.3430.0), but I was able to verify that the fix worked with the Windows Tip of Tree build available here:

https://download-chromium.appspot.com/

Build Revision: 558699 

Since the fix was a pure revert, I think it's safe to merge based on my verification here and in c#26.

Let me know.

Approving merge to M67 branch 3396 based on comment #28. Please merge ASAP and mark bug as fixed after the merge. Thank you.

Merge landed to 3396 here:

https://chromium-review.googlesource.com/c/chromium/src/+/1059736

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/8ce02ad56a451bfc047ccf01f38db58d5fc7c37c

commit 8ce02ad56a451bfc047ccf01f38db58d5fc7c37c
Author: Tommy Li <tommycli@chromium.org>
Date: Tue May 15 15:42:15 2018

Revert "Views: Turn on InkDropMasks for Windows."

This reverts commit a6de7e84dde8bd13f511bb5c09acb5a0eb8a747a.

Reason for revert: Makes extension popups blurry with non-integral
scale factors.

Bug:  824963 

Original change's description:
> Views: Turn on InkDropMasks for Windows.
>
> It seems to "just work".
>
> Tested on:
>  - Windows 10
>  - Windows 10 with --disable-gpu
>  - Windows 7
>  - Windows 7 Classic mode (Aero disabled)
>
> Bug: 713359
> Change-Id: I04466aab7e978ad51e5e579488e29789cda9ab72
> Reviewed-on: https://chromium-review.googlesource.com/961552
> Commit-Queue: Tommy Li <tommycli@chromium.org>
> Reviewed-by: Mohsen Izadi <mohsen@chromium.org>
> Reviewed-by: Trent Apted <tapted@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#543785}

TBR=tapted@chromium.org,mohsen@chromium.org,tommycli@chromium.org

# Not skipping CQ checks because original CL landed > 1 day ago.

Bug: 713359
Change-Id: I854e2315e5cd73c7aca67f0d7d226cb67102ff32
Reviewed-on: https://chromium-review.googlesource.com/1058289
Commit-Queue: Trent Apted <tapted@chromium.org>
Reviewed-by: Tommy Li <tommycli@chromium.org>
Reviewed-by: Trent Apted <tapted@chromium.org>
Cr-Original-Commit-Position: refs/heads/master@{#558526}(cherry picked from commit 13549a45248294edd44aaac6000ffd74887e1e94)
Reviewed-on: https://chromium-review.googlesource.com/1059736
Cr-Commit-Position: refs/branch-heads/3396@{#602}
Cr-Branched-From: 9ef2aa869bc7bc0c089e255d698cca6e47d6b038-refs/heads/master@{#550428}
[modify] https://crrev.com/8ce02ad56a451bfc047ccf01f38db58d5fc7c37c/ui/views/animation/ink_drop_host_view.cc
[modify] https://crrev.com/8ce02ad56a451bfc047ccf01f38db58d5fc7c37c/ui/views/controls/native/native_view_host_aura.cc

Note that this bug isn't fixed, just that enabling layer masks has been reverted.  Issue 843250  tracks fixing the underlying bug (did not reuse this bug as it has a ton of labels applied to it).

Able to reproduce the issue on chrome version 67.0.3378.0.
Verified the fix on Ubuntu 14.04 and Windows 10 using Chrome version #67.0.3396.48 as per the comment #0.
Attaching screenshot for reference.
Observed that "Text, images, borders have sharp edges"
Hence, the fix is working as expected.
Adding the verified label.

Thanks...!!

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All extension popups are blurred again with chrome://flags/#secondary-ui-md enabled and default on 70.0.3498.0 (as well as 69)
But works fine on 68.0.3440.68 and 67.0.3396.99