Is it only on Linux? Was chrome://settings/passwords completely empty? Did they see a prompt to unlock the Keyring?

A user actually also reported a case on Mac.
I don't know if they saw a keyring unlock prompt, but I don't usually see one when I start chrome or use the credential api on linux.
One person mentioned did mention that chrome://settings/passwords was empty.

Are there any logs or other information that would be useful to collect next time someone hits this? I think everyone I know of who has hit is has worked around by restarting chrome, but someone seems to report an issue every couple days so there will probably be another chance to collect logs soon if needed.

Let's not mix different bugs. Mac is Issue 171925. The questions to ask are
- Does the Keychain unlock automatically on startup?
- Was there any prompt to unlock the Keychain?
- Were there Mac updates, restarts before the issue happened.

Regarding Linux:
- What is the status of the Keyring? Unlocked automatically on restart? ('seahorse' is the name of the app to check it).
- when it happens again it's useful to try to save the credential on a a testing page https://rsolomakhin.github.io/autofill/ (there is no API, just a form submission). Did the credential appear in the Keyring? Are other existing credentials displayed on chrome://settings/passwords? What is the status of passwords on chrome://sync-internals/?

> What is the status of the Keyring? Unlocked automatically on restart?
seahorse didn't prompt to unlock or anything so yes it automatically unlocks?

> https://rsolomakhin.github.io/autofill/
Saw password save popup on submit; however the passwords were not automatically filled upon re-navigating back to the form.

> Did the credential appear in the Keyring?
No

> Are other existing credentials displayed on chrome://settings/passwords?
None
auto sign-in and offer to save passwords are checked

> What is the status of passwords on chrome://sync-internals/?
Error: MergeDataAndStartSyncing@../../components/password_manager/core/browser/password_syncable_service.cc:149, datatype error was encountered: Failed to get passwords from store.
status is: Not Running
Group Type: Group Passive

Any other info that would be useful to collect

Christos, please lead the investigation.

> seahorse didn't prompt to unlock or anything so yes it automatically unlocks?

I still think it might be a problem with keyring. Please confirm that they were able to open a keyring and view a password. There should be at least one entry, named "Chrome safe storage". Keep in mind that Seahorse prompts to unlock when you try to read the credentials, not when you simply start it. Please confirm that you are able to find and view this entry without an unlock prompt.
Also, what is the name of the keyring? Is it "Login"?

>Any other info that would be useful to collect
Is it possible to get logs from a user? Specifically, it would be useful if they recreated the problem on https://rsolomakhin.github.io/autofill/ when running Chrome as such:
google-chrome --enable-logging --vmodule=*key_storage*,*password_store*=1
The logs are typically in ~/.config/google-chrome/chrome_debug.log
If it's not there, they can find the location of their Chrome data folder in chrome://version.

Actually, if we can get logs, lets expand the logging a bit

google-chrome --enable-logging --vmodule=*key_storage*,*password_store*,*native_backend*=1

That would also give us what error keyring returns, if that's where the problem occurs. Thanks!

See Chrome Mac forum thread
  https://productforums.google.com/forum/#!topic/chrome/nEz4AGsl0no
I've tagged this as a 'main' thread on ~15 threads, and put short summaries in the main thread.  Sorry I was only looking for Mac reports.

The first pattern I saw was new Macs either new hardware or new Chrome installs.  I think this may be a red-herring.

Next pattern is regression on 66.0.3359.181 - Some users reporting 'since last update'.

There were a couple of cases linked to Mac security update or keychain repair.

It's not just new passwords. Chrome Settings...>Manage Passwords is empty but passwords.google.com is OK.

Use this forum mac passwd search to find cases
https://productforums.google.com/forum/#!topicsearchin/chrome/password$20category$3A(mac)%7Csort:date
or mac autofill - not as specific, but more cases..
https://productforums.google.com/forum/#!topicsearchin/chrome/autofill$20category$3A(mac)%7Csort:date

I'm posting the log request to the 'main' thread
  https://productforums.google.com/forum/#!topic/chrome/nEz4AGsl0no

Issue 845680 attributes password autofill loss to sync failure.  An attached sync-internals dump and screenshot shows a password sync error.

Can I have a few lines of instructions for the AutoFill Smoke Test that I can pass on to users?  Looks like they should complete a few sections and submit with logging enabled?

Re: overlap with Issue 171925
-This is a persistent user failure.  Broken users stay broken (until..?)
-only 3-4 of the 20 user reports I scanned mentioned keychain maintenance.

I'm seeing new reports almost hourly, but very few repeat comments or followup (5 / 20).  It's possible that sync recovers eventually.

vasi@ - When there's been a Mac or keychain update recently, is there a cleanup to fix Chrome access with the new keychain key?  Anything better than: change the Keychain settings so that it unlocks automatically (on OS user sign in)?

Let's keep this issue Linux only. For Mac there is Issue 171925.

See also Mac sync issue 845680 for recent, possibly M66..181 regression issues and (my) master forum thread
  https://productforums.google.com/forum/#!topic/chrome/nEz4AGsl0no

The incidence of password missing reports seems to have increased since the Mac 66.0.3359.181 release, but that's largely subjective.

Issue 171925 is historic, dating back several years.  It's hard to identify the latest trends there.  Issue 845680 seems to reflect the recent failure mode(s) more clearly.

Re: keychain: How can a user determine if their (which?) keychain is open for Chrome access? 
If healthy, can they see the (presence of) Chrome site passwords in the keychain?

I commented on Issue 845680. The passwords are not stored in the Keychain, only the encryption key.

vasi@ #15: OK 

Re: issue 171925: See my cmt there: You/vasi meant? Passwords saved in keychain - Chrome Safe Storage and needs login keychain (opened) and (original) key to decrypt?