Correction:
Step 2:Navigate to chrome://md-settings/content/cookies,click on 'add' button under clear on exit section.

This is a regression issue broken in 'M56' and below is the manual regression range:
Good Build: 56.0.2915.0
Bad Build:  56.0.2916.0

[mac triage] -> dbeam for triage

Narrow bisect
https://chromium.googlesource.com/chromium/src/+log/ad8a4ece43e32abb8bccacd89e382ae17afad8c2..0643d7f805b69c2fd595540791dc6a62ca195254?pretty=fuller&n=50

Suspecting: 431449 ?

dschuyler@/dpapad@: any ideas on what's going on here?  this does seem kind of unexpected, but I also don't generally understand the incognito content settings stuff that well

This is very related to  issue 680619 . When an incognito window is open, the exceptions list needs to be updated with any exceptions that only refer to incognito, and vice versa, when an incognito window is closed, those exceptions should be removed from the list. Well, at least this is how the old Options seems to handle Incognito-only exceptions.

I think comment #7 is on the money. I've been able to reproduce this issue, but it seems intermittent (so maybe there's a race condition somewhere). I'll look into it further, just making a quick update here.

Since this is not blocking crbug 671375, I'm un-starting this. To be resumed some other day.

The issue in #8 was fixed earlier, I believe.

What is left is that parts of the code omit session only from incognito session only options. Either this bug is that a user can set the incognito session only checkbox for a session only exception (and the fix is to remove that checkbox in that case); or the bug is that session only exceptions are not allowed for incognito.

There seems to be clear intent to prevent session only incognito session exceptions, so I'll go that way. Let me know if it should go the other way.

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/dfa9a8f45b3152616eabe23803befcb0673317f6

commit dfa9a8f45b3152616eabe23803befcb0673317f6
Author: dschuyler <dschuyler@chromium.org>
Date: Fri Apr 14 00:54:12 2017

[MD settings] hide option for incognito on session only exceptions

This CL removes the checkbox for 'incognito session only' from the add
site exception dialog for 'session only' exceptions.

BUG= 685027 
CQ_INCLUDE_TRYBOTS=master.tryserver.chromium.linux:closure_compilation

Review-Url: https://codereview.chromium.org/2817103002
Cr-Commit-Position: refs/heads/master@{#464634}

[modify] https://crrev.com/dfa9a8f45b3152616eabe23803befcb0673317f6/chrome/browser/resources/settings/site_settings/add_site_dialog.html
[modify] https://crrev.com/dfa9a8f45b3152616eabe23803befcb0673317f6/chrome/browser/resources/settings/site_settings/add_site_dialog.js
[modify] https://crrev.com/dfa9a8f45b3152616eabe23803befcb0673317f6/chrome/browser/resources/settings/site_settings/site_list.js