Cookies could be cleared at shutdown if...

• On the Options page, Privacy panel (you might need to select "Firefox will: Use custom settings for history" to check these details):
  • "Always use private browsing mode" is enabled
  • "Keep until: I close Firefox" is set, and the site exception is "Allow for Session" instead of "Allow" (from your description, this is not the issue)
  • "Clear history when Firefox closes" is enabled, and when you click the Settings button to the right, there is a checkmark for Cookies

• An extension is clearing cookies

• An external security/privacy/utility program cleans up your browser data between sessions

Could any of those be a factor?

Thanks for the reply. I'm assuming your referring to the Privacy options. I *had* Use Tracking protection in private windows checked, but I don't have "do not track" checked. I unchecked Tracking Protection, but still had to sign in again here to reply.

I did have "keep cookies until I close Firefox. But I changed to until they expire before I returned here.

I've never had "Clear history" checked."

What extension would clear cookies? Where do I find that?

Your last item.... I have CCleaner doing an autoclean each time I close the browser. But at least one of the website is on CCleaners's "Cookies to Keep" list, and it's still asking me to sign in each time I go there. So I'm not sure if CCleaner is the culprit.

KJSS said

I *had* Use Tracking protection in private windows checked, but I don't have "do not track" checked. I unchecked Tracking Protection, but still had to sign in again here to reply.

Those shouldn't affect cookies.

What extension would clear cookies? Where do I find that?

Usually it would be an add-on with cookie(s) or privacy in its name. Not something you would have installed by accident.

You can view, disable, and often remove unwanted or unknown extensions on the Add-ons page. Either:

• Ctrl+Shift+a (Mac: Command+Shift+a)
• "3-bar" menu button (or Tools menu) > Add-ons

In the left column, click Extensions. Then cast a critical eye over the list on the right side. Any potential suspects?

I have CCleaner doing an autoclean each time I close the browser. But at least one of the website is on CCleaners's "Cookies to Keep" list, and it's still asking me to sign in each time I go there. So I'm not sure if CCleaner is the culprit.

Well... that seems easy to test by exempting Firefox from the clean-out. If you restore the "Keep until: I close Firefox" option, you wouldn't have many for CCleaner to clean up, anyway.

Hello,

Only 3 extensions, all relating to password controls.

I'll experiment with CCleaner and Firefox, although it's so much easier to have Firefox do it automatically.

Okay, I removed Firefox from CCleaner's autoclean, then I closed the browser. When I returned here, I'm still logged in. But when I went to the other website I've used a few times today, I was not logged in.

Really strange. I'll contact CCleaner. Thanks much.