preference to restore previous session option does not save and browsing history is gone each time firefox closes on my macbook 的最新解答https://support.mozilla.org/zh-TW/questions/12849372020-04-19T04:20:08-07:00Have you copied the firefox.app file to the applications folder on your Mac or are you just opening 2020-04-19T04:20:08-07:00ComputerWhizhttps://support.mozilla.org/zh-TW/questions/1284937#answer-1307071<p>Have you copied the <code>firefox.app</code> file to the <code>applications</code> folder on your Mac or are you just opening Firefox directly from the downloaded <code>.dmg</code> file?
</p><p>You need to copy the <code>firefox.app</code> file to the <code>applications</code> folder or else Firefox will constantly be detected as a new installation and will replace your settings with the default settings by creating a new blank profile. See <a href="/en-US/kb/how-download-and-install-firefox-mac" rel="nofollow">How to download and install Firefox on Mac</a>.
</p><p>Hope this helps.
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