Able to reproduce the issue on chrome reported version# 70.0.3538.77 and on latest chrome# 72.0.3604.0 using Windows-10, Mac 10.12.6 and Ubuntu 14.04 with steps provided in comment# 0. As this issue is seen from M-69(From introduction of Material Design), hence considering this issue as Non-Regression and marking it as untriaged.

Thanks!

Hmmmm. This wasn't a problem in the Cocoa browser because Cocoa popup menus do not work this way (i.e. they don't open until clicked). Maybe we can always position below for this case - I'll take a look.

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/df1012dd8ee8b887f87383d6649e209e45bc6ed0

commit df1012dd8ee8b887f87383d6649e209e45bc6ed0
Author: Elly Fong-Jones <ellyjones@chromium.org>
Date: Wed Nov 14 18:18:36 2018

views: don't allow bookmark menus to be repositioned next to the anchor

Doing this prevents easy "scrubbing" through the bookmark bar menus, since the
newly-appearing menu draws over the top of the adjacent bookmark buttons.

Bug:  902344 
Change-Id: Ief783f4b417810416821b717f92f796b4e6b07e6
Reviewed-on: https://chromium-review.googlesource.com/c/1335870
Commit-Queue: Elly Fong-Jones <ellyjones@chromium.org>
Reviewed-by: Scott Violet <sky@chromium.org>
Cr-Commit-Position: refs/heads/master@{#608049}
[modify] https://crrev.com/df1012dd8ee8b887f87383d6649e209e45bc6ed0/chrome/browser/ui/views/bookmarks/bookmark_menu_controller_views.cc
[modify] https://crrev.com/df1012dd8ee8b887f87383d6649e209e45bc6ed0/chrome/browser/ui/views/bookmarks/bookmark_menu_controller_views.h
[modify] https://crrev.com/df1012dd8ee8b887f87383d6649e209e45bc6ed0/ui/views/controls/menu/menu_controller.cc
[modify] https://crrev.com/df1012dd8ee8b887f87383d6649e209e45bc6ed0/ui/views/controls/menu/menu_delegate.cc
[modify] https://crrev.com/df1012dd8ee8b887f87383d6649e209e45bc6ed0/ui/views/controls/menu/menu_delegate.h

***UI Mass Triage***

Since work is in progress, adding appropriate labels.

Able to reproduce the issue on chrome reported version# 70.0.3538.77
Verified the fix on Mac 10.12.6, Windows-10 & Ubuntu 14.04 on Chrome version #72.0.3611.0 as per the comment#0
Attaching screen cast for reference.
Observed "Folders in the Bookmarks Bar generated a dropdown menu"
Hence, the fix is working as expected.
Adding the verified label.

Thanks!

Deleted: 902344.mp4 1.9 MB

	902344.mp4 1.9 MB View Download

Thanks for verifying!

Apologies, I am unused to tracking bugs in here and didn't realize the bug fix had been completed until I read the "verified" comment. 

I just now verified it too and it seems to work. My one concern is that it still adds very large and IMHO unnecessary up/down arrows to long menus, rather than just showing a menu and letting you scroll when you hit the bottom ala native macOS.

Any way to fix that too?

Deleted: Screen Shot 2018-11-15 at 10.57.17 AM.png 402 KB

	Screen Shot 2018-11-15 at 10.57.17 AM.png 402 KB View Download

#10: That would be a separate bug.

However, that scroll arrow matches what macOS native menus do. I've attached a screenshot of Safari's behavior as an example. Our arrows look a bit different but the behavior is basically an exact match as far as I can tell.

Deleted: Screen Shot 2018-11-16 at 7.59.24 AM.png 46.6 KB

	Screen Shot 2018-11-16 at 7.59.24 AM.png 46.6 KB View Download

OK, I'll file as a separate bug. I guess I am referring to the fact that when I am at the topmost item, the up-arrow is still present, unlike in Safari.

Thanks for fixing the scrubbing thing. Much obliged!

 Issue 917678  has been merged into this issue.