Restarting chrome fixed it. I guess I did something that caused this state.

This is probably not a regression so lowering priority.

Min, can you please take a look? Thanks!

msw, ideas?

oshima, any other clues about this? I presume this was on an internal display, not external? Do you use multiprofile? Any chance the mouse position was over the shelf? Does your samus suffer from occasional false touch events? (I have one with a flaky touch sensor that causes touch events near the bezel sometimes.)

Code for shelf fullscreen is at https://cs.chromium.org/chromium/src/ash/shelf/shelf_layout_manager.cc?q=shelf_layout_manager.cc&sq=package:chromium&l=1097

(Also just FYI for Min, there is a different between HTML fullscreen that YouTube uses and the regular immersive fullscreen you get when hitting the fullscreen keyboard key.)

oshima@, can you still repro it? What I tried in 62.0.3188.0 on caroline
1. open the youtube
2. click fullscreen keyboard key

Or make the video in youtube page fullscreen

Shelf will be hidden. 

It happened with non immersive fullscreen (html5 fullscreen) where you can't show the shelf, so I believe this has nothing to do with events.

I guess the code that detect fullscreen mode for shelf was somehow not working correctly.

https://cs.chromium.org/chromium/src/ash/wm/workspace_controller.cc?rcl=3e8cc0d744079b603ce80a4201f3f0e768392ddf&l=56

It just happened again.

Looks like the window's ignored_by_shelf is set to true. Maybe someone sets it temporarily but didn't set it back to false.

Found the bug. Will send CL shortly.

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/ea65a745e112a8585a75b15e18c4f7dbc72fa13e

commit ea65a745e112a8585a75b15e18c4f7dbc72fa13e
Author: Mitsuru Oshima <oshima@chromium.org>
Date: Fri Aug 18 19:01:14 2017

Restore minimized window's ignored_by_shelf state correctly

when exiting overview mode

BUG= 756313 
TEST=covered by unit test (reused old disabled test)

Change-Id: I93bffc61b12b03a25dba36a18d0ea4596dd24297
Reviewed-on: https://chromium-review.googlesource.com/620151
Reviewed-by: Mitsuru Oshima <oshima@chromium.org>
Reviewed-by: Ahmed Fakhry <afakhry@chromium.org>
Commit-Queue: Mitsuru Oshima <oshima@chromium.org>
Cr-Commit-Position: refs/heads/master@{#495637}
[modify] https://crrev.com/ea65a745e112a8585a75b15e18c4f7dbc72fa13e/ash/wm/overview/scoped_transform_overview_window.cc
[modify] https://crrev.com/ea65a745e112a8585a75b15e18c4f7dbc72fa13e/ash/wm/overview/window_selector_unittest.cc

It's probably too late to merge to 60, but trying anyway :)

Approving merge to M61 Chrome OS.

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/bc7e55d2f5c9a42ef7fdf253b9e0eca77e602d2e

commit bc7e55d2f5c9a42ef7fdf253b9e0eca77e602d2e
Author: Mitsuru Oshima <oshima@chromium.org>
Date: Fri Aug 18 20:54:18 2017

Restore minimized window's ignored_by_shelf state correctly

when exiting overview mode

BUG= 756313 
TEST=covered by unit test (reused old disabled test)

(cherry picked from commit ea65a745e112a8585a75b15e18c4f7dbc72fa13e)

Change-Id: I93bffc61b12b03a25dba36a18d0ea4596dd24297
Reviewed-on: https://chromium-review.googlesource.com/620151
Reviewed-by: Mitsuru Oshima <oshima@chromium.org>
Reviewed-by: Ahmed Fakhry <afakhry@chromium.org>
Commit-Queue: Mitsuru Oshima <oshima@chromium.org>
Cr-Original-Commit-Position: refs/heads/master@{#495637}
Reviewed-on: https://chromium-review.googlesource.com/621968
Cr-Commit-Position: refs/branch-heads/3163@{#683}
Cr-Branched-From: ff259bab28b35d242e10186cd63af7ed404fae0d-refs/heads/master@{#488528}
[modify] https://crrev.com/bc7e55d2f5c9a42ef7fdf253b9e0eca77e602d2e/ash/wm/overview/scoped_transform_overview_window.cc
[modify] https://crrev.com/bc7e55d2f5c9a42ef7fdf253b9e0eca77e602d2e/ash/wm/overview/window_selector_unittest.cc

We are only accepting critical/security fixes for M60 at this point.
Based on the description, it does not seem to warrant cherry picking to M60 this late.

Let deliver this fix with M-61

This issue has been approved for a merge. Please merge the fix to any appropriate branches as soon as possible!

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This issue has been approved for a merge. Please merge the fix to any appropriate branches as soon as possible!

If all merges have been completed, please remove any remaining Merge-Approved labels from this issue.

Thanks for your time! To disable nags, add the Disable-Nags label.

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