Could reproduce in reported version 64.0.3282.186 and in latest canary build (67.0.3373.0)

Steps to reproduce:

1. Install a theme which invokes IDR_THEME_NTP_ATTRIBUTION

chrome-search://theme/IDR_THEME_NTP_ATTRIBUTION Returns correct attribution image. The display properties of the theme-attr div on newtab shows a z-index of -1 causing the div to not display properly

Sorry, I posted the first message with Opera.

Chrome version: 65.0.3325.162  Channel: stable
OS Version: 10.0

I can reproduce only in Chrome 65-67.

Bisect info: 522424 (good) - 522428 (bad)
https://chromium.googlesource.com/chromium/src/+log/99d09111..773623d2?pretty=fuller
Suspecting r522428 = 773623d293ed991e20596c4cb00e58610af5f395 = https://crrev.com/c/811185 by treib@chromium.org
"Local NTP: Load config.js dynamically"
Landed in 65.0.3288.0

Sorry woxxom you are correct, my initial test was in 65.0.3325.162 and not reporters 64.x version.

Able to reproduce the issue on Windows 10, mac 10.13.3 and Ubuntu 14.04 using chrome reported version #64.0.3282.186 and latest canary #67.0.3374.0.

Bisect Information:
=====================
Good build: 65.0.3287.0
Bad Build : 65.0.3288.0

Change Log URL: 
https://chromium.googlesource.com/chromium/src/+log/99d09111..773623d2?pretty=fuller

From the above change log suspecting below change
Change-Id: I609ef274325bddb49bcbe6e90d58d35b7a385920
Reviewed-on: https://chromium-review.googlesource.com/811185

treib@ - Could you please check whether this is caused with respect to your change, if not please help us in assigning it to the right owner.
Note: Adding stable blocker for M-65 as it seems to be a recent regression. Please feel free to remove the same if not appropriate.

Thanks...!!

I suspect this might be related to bug 755761/ bug 819781 .
Seems that currently the attribution doesn't appear on either the local or the remote NTP. The above CL could be the cause for the local NTP, but not for the remote one.

The "z-index: -1" is indeed weird and changing it makes the attribution visible again, but it's been there since forever, so something else must have triggered the change.

Also, M65 has been rolling out to stable for a while already, so this can't be a stable blocker for M65 anymore.

This was regressed in M64 and per comment #8, not a blocker for M65. Punting to M66.

Bisect #7 probably not correct as original issue is reported on M64.

kristipark@ is looking at theme-related bugs on NTP, so assigning to her for further review.

Per comment #2, this is indeed an M65 regression. Thank you +ajha@ for correcting me.

But still it is not a blocker for M65 per comment #8.

Friendly ping to get an update on this issue as it is marked as release block stable.

Thanks..!

I'm unsure what actually caused this to regress, but the z-index -1 of the attribution element places it behind the body element (i.e. the theme background) and causes it to be hidden.

Fixes for local and remote out for review:
https://chromium-review.googlesource.com/982553
http://cr/190644816

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/257158ee0bffba0301e3159eea056a0e118c4f0a

commit 257158ee0bffba0301e3159eea056a0e118c4f0a
Author: kristipark <kristipark@chromium.org>
Date: Wed Mar 28 20:08:14 2018

[Local NTP] Fix attribution hidden by theme background

Z-index -1 places the attribution behind the body element, which hides it when the body has a background color/image. Set ntp-contents z-index = 1 to prevent this.

Bug:  823068 
Cq-Include-Trybots: master.tryserver.chromium.linux:closure_compilation
Change-Id: I33af1427fcf57b6769cd98d4db1b891b4d93ae92
Reviewed-on: https://chromium-review.googlesource.com/982553
Commit-Queue: Kristi Park <kristipark@chromium.org>
Reviewed-by: Mathieu Perreault <mathp@chromium.org>
Cr-Commit-Position: refs/heads/master@{#546577}
[modify] https://crrev.com/257158ee0bffba0301e3159eea056a0e118c4f0a/chrome/browser/resources/local_ntp/local_ntp.css

Server side remote NTP fix is submitted and should roll out in a few days. Requesting M65 merge to fix local NTP.

M65 has been out since 03/06 and we're not planning any further M65 release unless critical issue arise. Please request a merge to M66 which is going to stable in few weeks. Thank you.

Able to reproduce this issue on reported version 65.0.3325.162 hence verifying the fix on latest canary.

Still attribution is seen missing in latest canary 67.0.3383.0 using Mac 13.03, Windows 10 and Ubuntu 14.04. Attaching screenshot for reference.

@kristipark: Please help in verifying the fix.

Deleted: 823068_67.0.3383.0.png 284 KB

	823068_67.0.3383.0.png 284 KB View Download

Changing merge request to M66.

c19: The local NTP fix has been pushed to Canary, which is reached using chrome-search://local-ntp/local-ntp.html. The remote NTP is served by GWS, so the fix should roll out sometime next week.

This bug requires manual review: M66 has already been promoted to the beta branch, so this requires manual review
Please contact the milestone owner if you have questions.
Owners: cmasso@(Android), cmasso@(iOS), josafat@(ChromeOS), abdulsyed@(Desktop)

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

Approved: branch:3359

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/c976556d63702d59736c380e645d9c9ea3199b3e

commit c976556d63702d59736c380e645d9c9ea3199b3e
Author: kristipark <kristipark@chromium.org>
Date: Fri Mar 30 22:29:46 2018

[Local NTP] Fix attribution hidden by theme background

Z-index -1 places the attribution behind the body element, which hides it when the body has a background color/image. Set ntp-contents z-index = 1 to prevent this.

Bug:  823068 
Cq-Include-Trybots: master.tryserver.chromium.linux:closure_compilation
Change-Id: I33af1427fcf57b6769cd98d4db1b891b4d93ae92
Reviewed-on: https://chromium-review.googlesource.com/982553
Commit-Queue: Kristi Park <kristipark@chromium.org>
Reviewed-by: Mathieu Perreault <mathp@chromium.org>
Cr-Original-Commit-Position: refs/heads/master@{#546577}(cherry picked from commit 257158ee0bffba0301e3159eea056a0e118c4f0a)
Reviewed-on: https://chromium-review.googlesource.com/988912
Cr-Commit-Position: refs/branch-heads/3359@{#513}
Cr-Branched-From: 66afc5e5d10127546cc4b98b9117aff588b5e66b-refs/heads/master@{#540276}
[modify] https://crrev.com/c976556d63702d59736c380e645d9c9ea3199b3e/chrome/browser/resources/local_ntp/local_ntp.css

Able to reproduce this issue on reported version 65.0.3325.162 hence verifying the fix on latest M-67 and latest M-66

Still attribution is seen missing in NTP on latest canary 67.0.3386.1 and 66.0.3359.80 using Mac 13.03, Windows 10 and Ubuntu 14.04. Attaching screenshot for reference.

@kristipark: Please help in verifying the fix.

Deleted: Screen Shot 2018-04-03 at 5.22.34 PM.png 223 KB

	Screen Shot 2018-04-03 at 5.22.34 PM.png 223 KB View Download

Apologies for the delay. The GWS server push is still in progress and is expected to finish later today or tomorrow. Local NTP should be verifiable using chrome-search://local-ntp/local-ntp.html.

Able to reproduce the issue on mac 10.13.3, win-10 and ubuntu 14.04 using chrome latest stable #65.0.3325.181 and bad build #65.0.3288.0 from comment #7.

Verified the fix on Mac 10.13.3, Win-10 and Ubuntu 14.04 using Chrome version #66.0.3359.81 as per the comment #0 and #25.
Attaching screen cast for reference.
Observed that attribution appeared on navigating to chrome-search://local-ntp/local-ntp.html
Hence, the fix is working as expected. 
Adding the verified labels.

Thanks...!!

Deleted: 823068.mp4 842 KB

	823068.mp4 842 KB View Download

The GWS server push has finished, and remote NTP should now be verifiable on all versions.