Unable to reproduce the issue on reported chrome version 67.0.3396.87 using Windows 10. Attaching screen-cast for reference.
Steps: 
---------
1. Launched reported chrome 
2. Navigated to URL " https://chrome.google.com/webstore/search/transparent%20theme%20for%20google "
3. Added theme to chrome >> " Aero Trans Brushed Metal Theme "
As we are able see Transparent Title bar.

@craigtumblison@chromium.org: Could you please review the attached screen-cast and confirm if anything being missed here. Also let us know the theme which user facing the issue.

Thanks..!

Deleted: 864709.mp4 3.9 MB

	864709.mp4 3.9 MB View Download

Thanks for the repro attempt!

In this instance, when we say "transparent" we're actually referring to something like this:
https://media.askvg.com/articles/images4/Transparent_Windows_8.png

I'm not sure what the specific steps are on Windows to enable this feature, and I'm not able to test as I don't have easy access to a Windows device for testing.

Is there any information we would be able to ask users for to assist with confirming if this is intended behavior or not?

Thanks again!

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

Tested the issue on reported chrome 67.0.3396.87 and latest stable 67.0.3396.99 using Windows 10. 
Steps:
---------
As per Comment #2,
1. Navigated to Windows theme 
2. Enabled transparent theme 
As we are seen that same behavior as per screenshot on comment #2 

@craigtumblison@chromium.org: Requesting you to please confirm the issue is specific to Windows theme/ Chrome browser theme and also confirm is that intended behavior or not?. Adding Needs-Feedback label to it.

Thanks...! 

#5: Thanks for the additional help! I believe that's the correct process, and the behavior you're seeing (after enabling transparency, still seeing a solid color) is what the user is reporting.

I'm not sure if that's intended behavior or not, but that *does* sound like the user reports - so I think you've reproduced the behavior in the report :)

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

As per comments #6 we are unable to reproduce the issue from our end. As we are adding windows theme by Navigating to >> Themes and Colors>> Enabled Transparency effects. As we are able to see theme on Windows but unable to see on Chrome. It seems to be an expected behavior. 

Hence requesting UI Team to have a look in to this issue.

Thanks...!

I don't know what this "transparent titlebars in Win 10" feature is.  If a user can clarify how they've enabled this feature, we can investigate.  I have "transparency effects" enabled in Windows 10's "Colors" panel, but don't see transparent titlebars on any native windows.

I'm willing to believe this is a custom win 10 titlebar regression, but without knowing what this effect is, I don't know how to help.

#10: Gotcha! I'm also unsure how the users are enabling the transparency.

I've reached out in this thread, and will follow up when I hear back:
- https://productforums.google.com/forum/#!topic/chrome/mHTCsNoPANg

Thanks!

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

(Setting back to needs feedback.)

Is it the 3rd-party utility mentioned in  bug 505013 , comment 52? We won't support that, since it's a 3rd-party utility.

Hey all,

I haven't heard back from the forum, and we've seen feedback levels drop. It's very possible the users were leveraging third-party software.

Since we can't confirm, I'm going to move this to WontFix.

Thanks!

I have yet to see anyone point out the most important part of this bug... in my experience...
This mostly affects "custom chrome themes" with transparency.

https://chrome.google.com/webstore/detail/chrome-glass/ceolnpdlbmchomeiaonlcpobfflboomd

Transparency no longer works since latest updates...

@16: That seems to be talking about CrOS, while this bug was about Windows.  Which OS are you on?