I don't see the firefox private browsing window why

These menu items are not available to you? support.mozilla.org/en-US/kb/private-browsing-use-firefox-without-history#w_how-do-i-open-a-new-private-window Also make sure you're not running in "always private" mode: support.mozilla.org/en-US/kb/private-browsing-use-firefox-without-history#w_can-i-set-firefox-to-always-use-private-browsing