By v2.0 introduces a built-in Session Restore feature, allowing the user to continue browsing from where they left off if browser restarts. Uses the first file to store session information used to recover after crashes, and the second files are created on a per-site basis to store cookie-related data.
https://news.softpedia.com/news/adjust-this-setting-before-firefox-wears-off-your-ssd-drive-508665.shtml
[code] about:config browser.sessionstore.interval change it to 3600000 for 1h [/code]
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