Unable to reproduce the issue on chrome reported version 65.0.3325.88 using windows-10 with steps mentioned below:
1) Launched chrome reported version, dragged and dropped the test.html file provided in comment#0
2) Opened Devtools > Performance tab and clicked on start
3) Scrolled and hovered the many times over the text field, observed smooth scrolling and hovered background appears without any delays
4) clicked on stop performance recording and observed smooth scrolling and hovering, didn't observed "Update layer tree records"

@Reporter:
Please find the attached screen cast for your reference and let us know if we missed anything in reproducing this issue. Try to test this issue by creating new person with no apps and extensions in it and le tus know if the issue still persists.

Thanks! 

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I am also experiencing this issue. Here are screencasts in stable and beta versions.

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Deleted: 814673_65.0.3325.88.mp4 2.6 MB

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@viswa.karala@chromium.org, thank you for feedback. I did some investigations and found that you tried to reproduce this issue in different Chrome version that I have. My Chrome version string displayed on "chrome://version" is "65.0.3325.88 (Official Build) beta (64-bit)", please look a the attached screen shot. Version displayed on your screen cast does not contain 'beta' string and looks like stable (strange, 65 stable is not published yet?..)

I installed my Chrome 65 beta version from official site at "https://www.google.com/chrome/browser/beta.html". The problem is here, so now i am not sure - will this problem also persist in Stable or not..

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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

Able to reproduce in Chrome 65 and 66.

Bisect info: 521694 (good) - 521706 (bad)
https://chromium.googlesource.com/chromium/src/+log/ac47dc85..bcb8fea0?pretty=fuller
Suspecting r521704 = a3ce2d3110a3f9177a41935daadd43ede72db553 = https://crrev.com/c/793973 by yigu@chromium.org
"Round the scroll offset synced back to main thread instead of flooring"
Landed in 65.0.3286.0

Confirmed by disabling the suspected CL and observing the bug is gone:
chrome --disable-blink-features=CompositeOpaqueFixedPosition

M65 Stable promotion is coming VERY soon next week. 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.

Tested the issue on chrome reported version 65.0.3325.88 using windows-10 with steps mentioned below:
1) Launched chrome reported version, dragged and dropped the test.html file provided in comment#0
2) Opened Devtools > Performance tab and clicked on start
3) Scrolled and hovered the many times over the text field, observed smooth scrolling and hovered background appears without any delays
4) clicked on stop performance recording and observed observed "Update layer tree records" in performance tab
Observations: Tested the issue on Stable 64.0.3282.186 and Latest chrome 66.0.3355.0, seen the same behaviour, even checked the issue on M60(60.0.3072.0) and observed the "Update layer tree" under performance tab.

Removing the Needs-Bisect label as per C#8 and attaching the screencast of chrome version# 60.0.3072.0 for reference.

Thanks!

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Will disable the feature mentioned in #8 to unblock the release and merge it back to M65 once the patch is eligible. 
Patch is up for review: https://chromium-review.googlesource.com/c/chromium/src/+/939585

This bug requires manual review: We are only 6 days from stable.
Please contact the milestone owner if you have questions.
Owners: cmasso@(Android), cmasso@(iOS), bhthompson@(ChromeOS), govind@(Desktop)

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

Please merge this as soon as possible.

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/69246b8974a267061fe1c1beab52bbcb17b474a7

commit 69246b8974a267061fe1c1beab52bbcb17b474a7
Author: Yi Gu <yigu@chromium.org>
Date: Tue Feb 27 21:47:34 2018

Disable runtime feature CompositeOpaqueFixedPosition

The feature caused performance regression on low dpi devices when a
fix positioned element contains too many children.

Temporarily disble it to unblock Stable release. Will address it through
https://crbug.com/816937.

Bug:  814673 
Change-Id: I6f0fea7d6b61f572b4d8da4e54c34d63cc5bc2f1
Reviewed-on: https://chromium-review.googlesource.com/939585
Commit-Queue: Yi Gu <yigu@chromium.org>
Reviewed-by: Robert Flack <flackr@chromium.org>
Reviewed-by: Scott Violet <sky@chromium.org>
Cr-Commit-Position: refs/heads/master@{#539552}
[modify] https://crrev.com/69246b8974a267061fe1c1beab52bbcb17b474a7/content/child/runtime_features.cc
[modify] https://crrev.com/69246b8974a267061fe1c1beab52bbcb17b474a7/content/public/common/content_features.cc

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/2214abb76685540cad140deffc5ebde1d56ca129

commit 2214abb76685540cad140deffc5ebde1d56ca129
Author: Yi Gu <yigu@chromium.org>
Date: Tue Feb 27 21:53:38 2018

Disable runtime feature CompositeOpaqueFixedPosition

The feature caused performance regression on low dpi devices when a
fix positioned element contains too many children.

Temporarily disble it to unblock Stable release. Will address it through
https://crbug.com/816937.

Bug:  814673 
Change-Id: I6f0fea7d6b61f572b4d8da4e54c34d63cc5bc2f1
Reviewed-on: https://chromium-review.googlesource.com/939585
Commit-Queue: Yi Gu <yigu@chromium.org>
Reviewed-by: Robert Flack <flackr@chromium.org>
Reviewed-by: Scott Violet <sky@chromium.org>
Cr-Original-Commit-Position: refs/heads/master@{#539552}(cherry picked from commit fc95fed8a9e4cadd5842241b0bb93a9991ff0021)
Reviewed-on: https://chromium-review.googlesource.com/939653
Reviewed-by: Stephen McGruer <smcgruer@chromium.org>
Cr-Commit-Position: refs/branch-heads/3325@{#612}
Cr-Branched-From: bc084a8b5afa3744a74927344e304c02ae54189f-refs/heads/master@{#530369}
[modify] https://crrev.com/2214abb76685540cad140deffc5ebde1d56ca129/content/child/runtime_features.cc
[modify] https://crrev.com/2214abb76685540cad140deffc5ebde1d56ca129/content/public/common/content_features.cc

Can this be marked as fixed if nothing is pending?

Though we should file a follow-on bug to fix the performance issue and re-enable the feature.

re #22, the bug will be tracked and handled via issue 816937.

As per comment#3 we are unable to reproduce the issue on chrome reported version and as per comemnt#12 we have tested this issue on chrome able to see the "Update layer tree" entries in Devtools > Performance tab. Tested the issue on latest chrome version 66.0.3357.0 using Ubuntu 14.04 with steps mentioned below:
1) Launched chrome reported version, dragged and dropped the test.html file provided in comment#0
2) Opened Devtools > Performance tab and clicked on start
3) Scrolled and hovered the many times over the text field, observed smooth scrolling and hovered background appears without any delays
4) clicked on stop performance recording and observed observed "Update layer tree records" in performance tab

@yigu:
Please check the attached screencast and please let us know the excepted behaviour and help in verifying the fix.

Thanks!

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As per comment#3 we are unable to reproduce the issue on chrome reported version and as per comemnt#12 we have tested this issue on chrome able to see the "Update layer tree" entries in Devtools > Performance tab. Tested the issue on chrome version 65.0.3325.106 using Mac 10.12.6 with steps mentioned below:
1) Launched chrome reported version, dragged and dropped the test.html file provided in comment#0
2) Opened Devtools > Performance tab and clicked on start
3) Scrolled and hovered the many times over the text field, observed smooth scrolling and hovered background appears without any delays
4) clicked on stop performance recording and observed observed "Update layer tree records" in performance tab

@yigu:
Please check the attached screencast and please let us know the excepted behaviour and help in verifying the fix.

Thanks!

Deleted: 814673.mp4 2.9 MB

	814673.mp4 2.9 MB View Download

FWIW I don't see any improvement in the official Canary 66.0.3357.0 which is based on r539659 so it should include the fix in #c18.
However, if I disable the feature manually, the bug is gone: chrome --disable-blink-features=CompositeOpaqueFixedPosition

re #26, there was a piece missing from the previous patch which fixed the hovering issue. Will fix it right away to completely disable the feature.

This bug requires manual review: We are only 5 days from stable.
Please contact the milestone owner if you have questions.
Owners: cmasso@(Android), cmasso@(iOS), bhthompson@(ChromeOS), govind@(Desktop)

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

 yigu@, could you pls point the cl you're requesting merge for based on comment #27?

re 29, https://chromium-review.googlesource.com/c/chromium/src/+/941262

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/5770b54a09c563cf56d7d2aaf7cdda80c59e1be1

commit 5770b54a09c563cf56d7d2aaf7cdda80c59e1be1
Author: Yi Gu <yigu@chromium.org>
Date: Wed Feb 28 15:45:59 2018

Disable runtime feature CompositeOpaqueFixedPosition

This patch fixed the missing part from the previous patch
https://crrev.com/c/939585 to completely disable the feature.

Bug:  814673 
Change-Id: Id14a32351d6153221aabf36dec506533ad07b437
Reviewed-on: https://chromium-review.googlesource.com/941262
Commit-Queue: Yi Gu <yigu@chromium.org>
Reviewed-by: Jeremy Roman <jbroman@chromium.org>
Reviewed-by: Robert Flack <flackr@chromium.org>
Cr-Commit-Position: refs/heads/master@{#539830}
[modify] https://crrev.com/5770b54a09c563cf56d7d2aaf7cdda80c59e1be1/third_party/WebKit/Source/platform/runtime_enabled_features.json5

This bug needs both the CLs from #18 and #31 to be fixed. Waiting for merge approval for the following patch which is cherry picked from #31. https://chromium-review.googlesource.com/c/chromium/src/+/941402

Please merge this as soon as possible.

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/e1bdf2f50853a0b1cf7fa6ed99634e54badc8b0f

commit e1bdf2f50853a0b1cf7fa6ed99634e54badc8b0f
Author: Yi Gu <yigu@chromium.org>
Date: Wed Feb 28 17:02:21 2018

Disable runtime feature CompositeOpaqueFixedPosition

This patch fixed the missing part from the previous patch
https://crrev.com/c/939585 to completely disable the feature.

Bug:  814673 
Change-Id: Id14a32351d6153221aabf36dec506533ad07b437
Reviewed-on: https://chromium-review.googlesource.com/941262
Commit-Queue: Yi Gu <yigu@chromium.org>
Reviewed-by: Jeremy Roman <jbroman@chromium.org>
Reviewed-by: Robert Flack <flackr@chromium.org>
Cr-Original-Commit-Position: refs/heads/master@{#539830}(cherry picked from commit 5770b54a09c563cf56d7d2aaf7cdda80c59e1be1)
Reviewed-on: https://chromium-review.googlesource.com/941402
Cr-Commit-Position: refs/branch-heads/3325@{#624}
Cr-Branched-From: bc084a8b5afa3744a74927344e304c02ae54189f-refs/heads/master@{#530369}
[modify] https://crrev.com/e1bdf2f50853a0b1cf7fa6ed99634e54badc8b0f/third_party/WebKit/Source/platform/runtime_enabled_features.json5

As per comment #3, #12, #24, #25, the issue is not reproducible at TE end.

yigu@ Request you to please check the issue on the latest Canary 66.0.3358.0 and help us in verifying the fix.

Thanks..

re #36, confirm that the issue cannot be reproduced on Canary 66.0.3358.0.

As per comment #36, the issue is not reproducible at TE end.

yigu@ Request you to please check the issue on the latest stable 65.0.3325.146 and help us in verifying the fix.

Thanks!

The fix has been verified on Linux, Win and Mac on the latest stable 65.0.3325.146.