You can't PB is already limited to what info saves and loads. And once closed everything is cleared. If your that afraid of the internet you IP already gives your activity away. Unless your a HedgeFund/Banker corporation or Government Head official your activity isn't going to peak those hackers interests.

so, it's either allowing all sites by default, or no sites at all ?

Was just thinking this would give users more control...

Rather than allow everything, then constantly block at will.

You'll want to read this about PB as well.

https://support.mozilla.org/en-US/kb/private-browsing-use-firefox-without-history

In PB mode extensions can't access local storage on the hard drive (browser-extension-data) and LastPass needs to access this folder in order to function properly. It is either use PB mode or the LP extension or other extensions that rely on storage.

TECH192 said

Is this possible, or only when using "Custom" ? (which would mean, it would save cookies for ALL sites,,, someting i'd rather not do, only just (one), which is why i'm using PB.

The Preferences page has been rearranged, so there are at least two relevant sections.

Default All Cookies to Session-only

The setting to dump cookies automatically at the end of your regular session is now here:

• Mac: "3-bar" menu button (or Firefox menu) > Preferences
• Windows: "3-bar" menu button (or Tools menu) > Options
• Linux: "3-bar" menu button (or Edit menu) > Preferences
• Any system: type or paste about:preferences into the address bar and press Enter/Return to load it

In the left column, click Privacy & Security, and on the right side, scroll down to the Cookies and Site Data section.

The checkbox for "Delete cookies and site data when Firefox is closed" works as follows:

(A) If the box is NOT checked, then Firefox lets sites specify how long Firefox will retain their cookies.

(B) If the box IS checked, then Firefox shortens the site's preferred expiration time to the end of the current session. You can let sites store persistent cookies by creating an exception using the Manage Permissions button. Format note, include the protocol, for example:

• https://mozilla.org => Allow
• http://mozillazine.org => Allow

Exceptions are only needed if you want to stay logged in to a site.

Block Third Party Tracking Cookies

If you scroll up to the Content Blocking section and choose Custom, you can block third party tracking cookies there. Unlike other sites, the sites on the trackers list won't even be able to set a session-only cookie.

Does that get close to what you're looking for?

Yes..

I would think more of "block and only exceptions on request"

Very similar routers works.. Block all by default, and user opens ports at will.

But I guess the same concept, transitioned to browsing, wouldn't work because too many sites would break.

However, since there is a PB mode anyway, this could be better than a more granular control of using "custom" and unchecking "Remember browsing history" and "Remember search and form history" to "simulate" the idea except everything is kept until session expires with more refined control f how they are kept or blocked.

Content blocking is effective, but not really desirable, as in most cases all users are waning is to allow "exceptions" yet still remain in that PB state..

Rather, instead you have a system where you allow everything, and "block sites" which is the total reversal of what people would use PB for.

Hi TECH192, the core feature of private browsing is that cookies and history are not written to disk. Browsing data is accumulated temporarily in memory for the duration of your private session (until all private windows are closed) instead of writing it to disk. In that respect, all private browsing cookies are session-only cookies that are dumped at the end of the private session. Cookies are not blocked unless you go further and change your settings to block cookies. As you point out, that can break many sites.