Question How does Gmail track my sign-in status ?

[Usjes]

Hi,

I'm trying to figure out how gmail keeps track of my signed in status. eg. if another site offers the option 'Sign in with Google' I enter my gmail credentials to get access to another site, if I then open Gmail in another tab it goes straight to my inbox (no credentials required) so it is clearly keeping track of the fact that I already logged in (albeit on another site). So, I'm trying to figure out how Google keeps track of my signed-in status ? I would have assumed it was via a cookie. So I go to Firefox -> preferences -> Privacy & Security -> Clear Data.
After this Firefox lists:
Cookies and Site Data (0 bytes)
Cached website content (0 bytes)
Yet if I open gmail in a new tab I'm still getting straight through to my inbox, no credentials required. So, how is Google doing this ? It's highly undesirable and very creepy. Or does this suggest a bug in Firefox (that its not actually clearing data as it should) ? I'm using version 87.0 on Ubuntu 18.04 LTS.

Thanks,

Usjes

 

[rgd1101]

on the back, it still google.

are you saving login/password? using any of the password extension?
using the firefox account thing?

mine always ask to login.

 

[Usjes]

on the back, it still google.

are you saving login/password? using any of the password extension?
using the firefox account thing?

mine always ask to login.

No, I have no extensions and I am not using any firefox account, so I don't understand where this information is being stored. I see only two possibilities:
(i) Google has found some loophole to create a 'cookie' that Firefox can't see
(ii) Firefox has a dangerous bug whereby it fails to delete cookies when you ask it to.

 

[rgd1101]

use the manual bar. try the clear recent history.
latest firefox?

I'm on windows. so maybe linux issue?

 

[Usjes]

use the manual bar. try the clear recent history.
latest firefox?

I'm on windows. so maybe linux issue?

Yes I also tried 'Clear recent History' instead of just 'Clear Data' but the result is the same, I remain signed in. I have to actually close the browser down and restart it before I get signed out.
It looks like version 88 has been released recently for Linux so I'll try that.