Hello, Try see [[Changes to toolbars and window sizes are not saved]]

In case you use "Clear history when Firefox closes" or otherwise clear history: *do not clear the Site Preferences *Tools > Options > Privacy > Firefox will: "Use custom settings for history": [X] "Clear history when Firefox closes" > Settings *https://support.mozilla.org/kb/remove-recent-browsing-search-and-download-history Clearing "Site Preferences" clears all exceptions for cookies, images, pop-up windows, software installation, passwords, and other website specific data. Clearing cookies will remove all specified (selected) cookies including cookies with an allow exception that you would like to keep. ---- You can use an extension to set a default font size and page zoom on web pages. *Default FullZoom Level: https://addons.mozilla.org/firefox/addon/default-fullzoom-level/ *NoSquint: https://addons.mozilla.org/firefox/addon/nosquint/