Thanks for filing the issue!

Tried checking the issue on reported chrome version 69.0.3497.100 using Windows 10 with the below mentioned steps.
1. Launched chrome
2. Set the flags as per c#0 in chrome://flags
3. Signed into chrome
4. Opened an other Window -> Opened multiple tabs (...50+ in each window)
We have not observed the overlapping of profile button over minimise button on any of the window.

@Reporter: Could you please check the same on a new profile without any apps & extensions and let us know if the issue still persists. Any further inputs from your end may be helpful.

I noticed number 5 wasn't go fullscreen.

I created a new profile, with only that open, so I'll correct the steps from c#2

1. Launched chrome
2. Set the flags as per c#0 in chrome://flags
3. Signed into chrome
4. Opened an other Window -> Opened multiple tabs
5. Went fullscreen

It doesn't occur until fullscreen is entered, and then exited.

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

I realizes after a nights sleep that what I had said was slightly inaccurate, so bear with me, I'm correcting it once more.

I had realized that it may have been considered I was talking about entering chrome in fullscreen, and not a video stream, which is what I had meant.

1. Launched chrome
2. Set the flags as per c#0 in chrome://flags
3. Signed into chrome
4. Go fullscreen on any video stream
5. Exit fullscreen

Tried checking the issue exactly as per the steps mentioned in C#5 using chrome version 69.0.3497.100 on Windows 10, still we didn't see the profile button overlapping with minimise button after exiting the full screen. Attaching the screen cast of the same for reference.

@Reporter: Could you please have a look at the screencast and let us know if we have missed in the process. 

Deleted: 892374.mp4 8.4 MB

	892374.mp4 8.4 MB View Download

Everything is indeed correct in that video, however, upon further research and testing on a few other computers, I believe it now to be related to the Windows 10 1809 feature update, as trying on a version of windows prior to 1809 with the same chrome version/flags/profiles works fine. Unfortunately that update has also been pulled now. I suppose I'll have to revert to a earlier version of windows for now.

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

From comment#7 the issue seems to be related to Windows update rather than with Chrome, hence removing Needs-Bisect label.

@Reporter: It is understood that the issue isn't with chrome, in that case could you please let us know if this issue can closed.

Thanks!

That is correct c#9, I have just reverted back to an earlier version of windows and it is working properly.

Go ahead and close it.

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

As per comment#10 by reporter closing this issue and marking it as Won't fix.

Thanks!