Interesting - I tried to reproduce this, but I couldn't get to the subpage if I didn't have a host device set. Would you mind providing more specific repro steps? What did you click to get to this subpage?

Jeese? What got you here?

While I can't reproduce this on my Nautilus running the latest dev build (70.0.3538.16), I can freely reproduce it on my Eve running the latest canary (71.0.3544.0).

To repro, forget any phones you have configured to work with Better Together, return to the top level Chrome OS Settings page, then click the white space around the title/value prop (to left of the setup button).

See attached screenshot.

Deleted: Screenshot 2018-09-15 at 9.50.20 AM.png 37.3 KB

	Screenshot 2018-09-15 at 9.50.20 AM.png 37.3 KB View Download

Weird - I cannot reproduce this issue. Let's wait a few days for a new canary push to see if you can repro it then.

That being said, it probably doesn't make sense to allow users to visit the subpage at all if there is no host device set. Maybe it would make sense to route users back to the top-level page if they try to open the subpage in this state. Thoughts?

Agreed, Kyle.

You're not supposed to be able to. Please let me know if you get there again. I'm adding some new logs https://chromium-review.googlesource.com/c/chromium/src/+/1227362 that should make this issue easier to debug

I missed something here: Jesse was seeing this because we were allowing the Settings item to route to the subpage regardless of the mode/host status. That issue was fixed so users cannot navigate to the subpage by clicking the item anymore unless the host is set. They could manually type in the address to sneak into the subpage, but I don't think it's worth spending the effort to make that impossible because it can't impact UX unless the user is intentionally messing with the UI.

Doesn't a click on a multi-device notification lead users to this page? What about if:

(1) Existing user notification is shown.
(2) User forgets device.
(3) User clicks on notification.

Wouldn't that lead us to a broken page?

Yeah, that's a good point. I'll make a CL to remove existing host notifications when there's no longer a verified host.

Sounds good, but I still think it makes sense to add a CL which prohibits users from going to the multi-device page when it is not applicable.

It should be as simple as inheriting RouteObserverBehavior and overriding currentRouteChanged() to navigate to the main screen if the route is not applicable.

I think we should just only do Kyle's suggestion in #13. Trying to address every individual edge case isn't worth our time.

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/5d6c5454385f30e67843a8c7e91eae9f719b1b3b

commit 5d6c5454385f30e67843a8c7e91eae9f719b1b3b
Author: Jordy Greenblatt <jordynass@chromium.org>
Date: Wed Oct 17 02:30:08 2018

[CrOS MultiDevice] Leave nested settings pages if no host is set

Some edge cases are leading the user to the settings subpage without a
host set. Because the subpage is designed for a set host, we want to
route the user to the main settings page (i.e. the 'Connected Devices'
section of the basic page) when this occurs.

This CL routes the user to the main page when a page content data
update reveals no host while they are on the any page below the main
page.

Bug:  884401 
Change-Id: Icf8aeb1f2c3b2a226f6f597135fa7ed2f96569f9
Reviewed-on: https://chromium-review.googlesource.com/c/1285209
Reviewed-by: Kyle Horimoto <khorimoto@chromium.org>
Commit-Queue: Jordy Greenblatt <jordynass@chromium.org>
Cr-Commit-Position: refs/heads/master@{#600254}
[modify] https://crrev.com/5d6c5454385f30e67843a8c7e91eae9f719b1b3b/chrome/browser/resources/settings/multidevice_page/BUILD.gn
[modify] https://crrev.com/5d6c5454385f30e67843a8c7e91eae9f719b1b3b/chrome/browser/resources/settings/multidevice_page/multidevice_page.js

Your change meets the bar and is auto-approved for M71. Please go ahead and merge the CL to branch 3578 manually. Please contact milestone owner if you have questions.
Owners: benmason@(Android), kariahda@(iOS), kbleicher@(ChromeOS), govind@(Desktop)

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

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/dfb84c979338ad21c3b63305b87ea36ed2631afd

commit dfb84c979338ad21c3b63305b87ea36ed2631afd
Author: Kyle Horimoto <khorimoto@google.com>
Date: Thu Oct 18 15:22:33 2018

[CrOS MultiDevice] Leave nested settings pages if no host is set

Some edge cases are leading the user to the settings subpage without a
host set. Because the subpage is designed for a set host, we want to
route the user to the main settings page (i.e. the 'Connected Devices'
section of the basic page) when this occurs.

This CL routes the user to the main page when a page content data
update reveals no host while they are on the any page below the main
page.

TBR=jordynass@chromium.org

(cherry picked from commit 5d6c5454385f30e67843a8c7e91eae9f719b1b3b)

Bug:  884401 
Change-Id: Icf8aeb1f2c3b2a226f6f597135fa7ed2f96569f9
Reviewed-on: https://chromium-review.googlesource.com/c/1285209
Reviewed-by: Kyle Horimoto <khorimoto@chromium.org>
Commit-Queue: Jordy Greenblatt <jordynass@chromium.org>
Cr-Original-Commit-Position: refs/heads/master@{#600254}
Reviewed-on: https://chromium-review.googlesource.com/c/1288714
Cr-Commit-Position: refs/branch-heads/3578@{#118}
Cr-Branched-From: 4226ddf99103e493d7afb23a4c7902ee496108b6-refs/heads/master@{#599034}
[modify] https://crrev.com/dfb84c979338ad21c3b63305b87ea36ed2631afd/chrome/browser/resources/settings/multidevice_page/BUILD.gn
[modify] https://crrev.com/dfb84c979338ad21c3b63305b87ea36ed2631afd/chrome/browser/resources/settings/multidevice_page/multidevice_page.js

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/9bc3529fa3e30165627cdb56d378c207dd118c8c

commit 9bc3529fa3e30165627cdb56d378c207dd118c8c
Author: Jordy Greenblatt <jordynass@chromium.org>
Date: Thu Oct 18 18:21:23 2018

[CrOS MultiDevice] Remove notifications after OOBE setup flow

At present, if a user turns down MultiDevice setup in OOBE, they will
see a notification prompting them to go through our regular setup flow.
In order to avoid spamming people with unwanted notifications, this CL
keeps track of if/when the user saw setup flow in OOBE and prevents
future setup prompting notifications if they have.

Bug:  892829 ,  884401 
Change-Id: I231a25d7879b37912c8594998578eea9afadbf5e
Reviewed-on: https://chromium-review.googlesource.com/c/1275432
Commit-Queue: Jordy Greenblatt <jordynass@chromium.org>
Reviewed-by: Colin Blundell <blundell@chromium.org>
Reviewed-by: Stefan Kuhne <skuhne@chromium.org>
Reviewed-by: Alexander Alekseev <alemate@chromium.org>
Reviewed-by: Kyle Horimoto <khorimoto@chromium.org>
Cr-Commit-Position: refs/heads/master@{#600833}
[modify] https://crrev.com/9bc3529fa3e30165627cdb56d378c207dd118c8c/chrome/browser/chromeos/BUILD.gn
[modify] https://crrev.com/9bc3529fa3e30165627cdb56d378c207dd118c8c/chrome/browser/chromeos/login/screens/multidevice_setup_screen.cc
[add] https://crrev.com/9bc3529fa3e30165627cdb56d378c207dd118c8c/chrome/browser/chromeos/multidevice_setup/oobe_completion_tracker_factory.cc
[add] https://crrev.com/9bc3529fa3e30165627cdb56d378c207dd118c8c/chrome/browser/chromeos/multidevice_setup/oobe_completion_tracker_factory.h
[modify] https://crrev.com/9bc3529fa3e30165627cdb56d378c207dd118c8c/chrome/browser/profiles/profile_impl.cc
[modify] https://crrev.com/9bc3529fa3e30165627cdb56d378c207dd118c8c/chromeos/services/multidevice_setup/BUILD.gn
[modify] https://crrev.com/9bc3529fa3e30165627cdb56d378c207dd118c8c/chromeos/services/multidevice_setup/DEPS
[modify] https://crrev.com/9bc3529fa3e30165627cdb56d378c207dd118c8c/chromeos/services/multidevice_setup/account_status_change_delegate_notifier_impl.cc
[modify] https://crrev.com/9bc3529fa3e30165627cdb56d378c207dd118c8c/chromeos/services/multidevice_setup/account_status_change_delegate_notifier_impl.h
[modify] https://crrev.com/9bc3529fa3e30165627cdb56d378c207dd118c8c/chromeos/services/multidevice_setup/account_status_change_delegate_notifier_impl_unittest.cc
[modify] https://crrev.com/9bc3529fa3e30165627cdb56d378c207dd118c8c/chromeos/services/multidevice_setup/multidevice_setup_impl.cc
[modify] https://crrev.com/9bc3529fa3e30165627cdb56d378c207dd118c8c/chromeos/services/multidevice_setup/multidevice_setup_impl.h
[modify] https://crrev.com/9bc3529fa3e30165627cdb56d378c207dd118c8c/chromeos/services/multidevice_setup/multidevice_setup_impl_unittest.cc
[modify] https://crrev.com/9bc3529fa3e30165627cdb56d378c207dd118c8c/chromeos/services/multidevice_setup/multidevice_setup_initializer.cc
[modify] https://crrev.com/9bc3529fa3e30165627cdb56d378c207dd118c8c/chromeos/services/multidevice_setup/multidevice_setup_initializer.h
[modify] https://crrev.com/9bc3529fa3e30165627cdb56d378c207dd118c8c/chromeos/services/multidevice_setup/multidevice_setup_service.cc
[modify] https://crrev.com/9bc3529fa3e30165627cdb56d378c207dd118c8c/chromeos/services/multidevice_setup/multidevice_setup_service.h
[modify] https://crrev.com/9bc3529fa3e30165627cdb56d378c207dd118c8c/chromeos/services/multidevice_setup/multidevice_setup_service_unittest.cc
[modify] https://crrev.com/9bc3529fa3e30165627cdb56d378c207dd118c8c/chromeos/services/multidevice_setup/public/cpp/BUILD.gn
[modify] https://crrev.com/9bc3529fa3e30165627cdb56d378c207dd118c8c/chromeos/services/multidevice_setup/public/cpp/multidevice_setup_client_impl_unittest.cc
[add] https://crrev.com/9bc3529fa3e30165627cdb56d378c207dd118c8c/chromeos/services/multidevice_setup/public/cpp/oobe_completion_tracker.cc
[add] https://crrev.com/9bc3529fa3e30165627cdb56d378c207dd118c8c/chromeos/services/multidevice_setup/public/cpp/oobe_completion_tracker.h

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/a66f261a11f550e1df334991c668ce5721ad960a

commit a66f261a11f550e1df334991c668ce5721ad960a
Author: Jordy Greenblatt <jordynass@chromium.org>
Date: Mon Oct 22 18:29:52 2018

[CrOS MultiDevice] Remove notifications after OOBE setup flow

At present, if a user turns down MultiDevice setup in OOBE, they will
see a notification prompting them to go through our regular setup flow.
In order to avoid spamming people with unwanted notifications, this CL
keeps track of if/when the user saw setup flow in OOBE and prevents
future setup prompting notifications if they have.

(cherry picked from commit 9bc3529fa3e30165627cdb56d378c207dd118c8c)

Bug:  892829 ,  884401 
Change-Id: I231a25d7879b37912c8594998578eea9afadbf5e
Reviewed-on: https://chromium-review.googlesource.com/c/1275432
Commit-Queue: Jordy Greenblatt <jordynass@chromium.org>
Reviewed-by: Colin Blundell <blundell@chromium.org>
Reviewed-by: Stefan Kuhne <skuhne@chromium.org>
Reviewed-by: Alexander Alekseev <alemate@chromium.org>
Reviewed-by: Kyle Horimoto <khorimoto@chromium.org>
Cr-Original-Commit-Position: refs/heads/master@{#600833}
Reviewed-on: https://chromium-review.googlesource.com/c/1289166
Reviewed-by: Ryan Hansberry <hansberry@chromium.org>
Cr-Commit-Position: refs/branch-heads/3578@{#232}
Cr-Branched-From: 4226ddf99103e493d7afb23a4c7902ee496108b6-refs/heads/master@{#599034}
[modify] https://crrev.com/a66f261a11f550e1df334991c668ce5721ad960a/chrome/browser/chromeos/BUILD.gn
[modify] https://crrev.com/a66f261a11f550e1df334991c668ce5721ad960a/chrome/browser/chromeos/login/screens/multidevice_setup_screen.cc
[add] https://crrev.com/a66f261a11f550e1df334991c668ce5721ad960a/chrome/browser/chromeos/multidevice_setup/oobe_completion_tracker_factory.cc
[add] https://crrev.com/a66f261a11f550e1df334991c668ce5721ad960a/chrome/browser/chromeos/multidevice_setup/oobe_completion_tracker_factory.h
[modify] https://crrev.com/a66f261a11f550e1df334991c668ce5721ad960a/chrome/browser/profiles/profile_impl.cc
[modify] https://crrev.com/a66f261a11f550e1df334991c668ce5721ad960a/chromeos/services/multidevice_setup/BUILD.gn
[modify] https://crrev.com/a66f261a11f550e1df334991c668ce5721ad960a/chromeos/services/multidevice_setup/DEPS
[modify] https://crrev.com/a66f261a11f550e1df334991c668ce5721ad960a/chromeos/services/multidevice_setup/account_status_change_delegate_notifier_impl.cc
[modify] https://crrev.com/a66f261a11f550e1df334991c668ce5721ad960a/chromeos/services/multidevice_setup/account_status_change_delegate_notifier_impl.h
[modify] https://crrev.com/a66f261a11f550e1df334991c668ce5721ad960a/chromeos/services/multidevice_setup/account_status_change_delegate_notifier_impl_unittest.cc
[modify] https://crrev.com/a66f261a11f550e1df334991c668ce5721ad960a/chromeos/services/multidevice_setup/multidevice_setup_impl.cc
[modify] https://crrev.com/a66f261a11f550e1df334991c668ce5721ad960a/chromeos/services/multidevice_setup/multidevice_setup_impl.h
[modify] https://crrev.com/a66f261a11f550e1df334991c668ce5721ad960a/chromeos/services/multidevice_setup/multidevice_setup_impl_unittest.cc
[modify] https://crrev.com/a66f261a11f550e1df334991c668ce5721ad960a/chromeos/services/multidevice_setup/multidevice_setup_initializer.cc
[modify] https://crrev.com/a66f261a11f550e1df334991c668ce5721ad960a/chromeos/services/multidevice_setup/multidevice_setup_initializer.h
[modify] https://crrev.com/a66f261a11f550e1df334991c668ce5721ad960a/chromeos/services/multidevice_setup/multidevice_setup_service.cc
[modify] https://crrev.com/a66f261a11f550e1df334991c668ce5721ad960a/chromeos/services/multidevice_setup/multidevice_setup_service.h
[modify] https://crrev.com/a66f261a11f550e1df334991c668ce5721ad960a/chromeos/services/multidevice_setup/multidevice_setup_service_unittest.cc
[modify] https://crrev.com/a66f261a11f550e1df334991c668ce5721ad960a/chromeos/services/multidevice_setup/public/cpp/BUILD.gn
[modify] https://crrev.com/a66f261a11f550e1df334991c668ce5721ad960a/chromeos/services/multidevice_setup/public/cpp/multidevice_setup_client_impl_unittest.cc
[add] https://crrev.com/a66f261a11f550e1df334991c668ce5721ad960a/chromeos/services/multidevice_setup/public/cpp/oobe_completion_tracker.cc
[add] https://crrev.com/a66f261a11f550e1df334991c668ce5721ad960a/chromeos/services/multidevice_setup/public/cpp/oobe_completion_tracker.h

The following revision refers to this bug: 
https://chromium.googlesource.com/chromium/src.git/+/a66f261a11f550e1df334991c668ce5721ad960a

Commit: a66f261a11f550e1df334991c668ce5721ad960a
Author: jordynass@chromium.org
Commiter: hansberry@chromium.org
Date: 2018-10-22 18:29:52 +0000 UTC

[CrOS MultiDevice] Remove notifications after OOBE setup flow

At present, if a user turns down MultiDevice setup in OOBE, they will
see a notification prompting them to go through our regular setup flow.
In order to avoid spamming people with unwanted notifications, this CL
keeps track of if/when the user saw setup flow in OOBE and prevents
future setup prompting notifications if they have.

(cherry picked from commit 9bc3529fa3e30165627cdb56d378c207dd118c8c)

Bug:  892829 ,  884401 
Change-Id: I231a25d7879b37912c8594998578eea9afadbf5e
Reviewed-on: https://chromium-review.googlesource.com/c/1275432
Commit-Queue: Jordy Greenblatt <jordynass@chromium.org>
Reviewed-by: Colin Blundell <blundell@chromium.org>
Reviewed-by: Stefan Kuhne <skuhne@chromium.org>
Reviewed-by: Alexander Alekseev <alemate@chromium.org>
Reviewed-by: Kyle Horimoto <khorimoto@chromium.org>
Cr-Original-Commit-Position: refs/heads/master@{#600833}
Reviewed-on: https://chromium-review.googlesource.com/c/1289166
Reviewed-by: Ryan Hansberry <hansberry@chromium.org>
Cr-Commit-Position: refs/branch-heads/3578@{#232}
Cr-Branched-From: 4226ddf99103e493d7afb23a4c7902ee496108b6-refs/heads/master@{#599034}

The following revision refers to this bug: 
https://chromium.googlesource.com/chromium/src.git/+/dfb84c979338ad21c3b63305b87ea36ed2631afd

Commit: dfb84c979338ad21c3b63305b87ea36ed2631afd
Author: khorimoto@google.com
Commiter: khorimoto@chromium.org
Date: 2018-10-18 15:22:33 +0000 UTC

[CrOS MultiDevice] Leave nested settings pages if no host is set

Some edge cases are leading the user to the settings subpage without a
host set. Because the subpage is designed for a set host, we want to
route the user to the main settings page (i.e. the 'Connected Devices'
section of the basic page) when this occurs.

This CL routes the user to the main page when a page content data
update reveals no host while they are on the any page below the main
page.

TBR=jordynass@chromium.org

(cherry picked from commit 5d6c5454385f30e67843a8c7e91eae9f719b1b3b)

Bug:  884401 
Change-Id: Icf8aeb1f2c3b2a226f6f597135fa7ed2f96569f9
Reviewed-on: https://chromium-review.googlesource.com/c/1285209
Reviewed-by: Kyle Horimoto <khorimoto@chromium.org>
Commit-Queue: Jordy Greenblatt <jordynass@chromium.org>
Cr-Original-Commit-Position: refs/heads/master@{#600254}
Reviewed-on: https://chromium-review.googlesource.com/c/1288714
Cr-Commit-Position: refs/branch-heads/3578@{#118}
Cr-Branched-From: 4226ddf99103e493d7afb23a4c7902ee496108b6-refs/heads/master@{#599034}