Firefox is supposed to remember the zoom level for that page but some other users also reported that their Firefox is not remembering. Although we haven't discovered the reason for it, you could look into the workarounds discussed there: [https://support.mozilla.org/questions/1025414 How do I change the default zoom for New Tab only?]

What is the setting of the browser.newtab.preload pref on the <b>about:config</b> page? You can try to toggle this pref. Also make sure this pref has the default value. *http://kb.mozillazine.org/browser.zoom.siteSpecific You can open the <b>about:config</b> page via the location/address bar. You can accept the warning and click "I'll be careful" to continue. *http://kb.mozillazine.org/about:config ----- *http://kb.mozillazine.org/Zoom_text_of_web_pages *http://kb.mozillazine.org/browser.zoom.full *http://kb.mozillazine.org/toolkit.zoomManager.zoomValues