PUBLIC MARKS from decembre with tags FIR57 & firefox

This extension makes easier to use more profiles in Firefox and Thunderbird. This extension will not be compatible with Firefox versions > 52, due to the changes decided by Mozilla in extensions support with Firefox. Alternative : In firefox 57 or quantum you open a new tab, write about:profiles and manages your profile

How to enable Firefox WebExtensions on Mozilla websites (in https://www.ghacks.net/2017/10/27/how-to-enable-firefox-webextensions-on-mozilla-websites/): - Load about:config in the Firefox web browser. - You can run a search for just to make sure it does not exist: privacy.resistFingerprinting.block_mozAddonManager. It does not in the most recent Firefox Nightly builds at the time of writing. - Right-click in the part of the window that lists the preferences, and select New > Boolean from the context menu. - Name the new Boolean value: privacy.resistFingerprinting.block_mozAddonManager. - Set its value to true.

userChrome.css is a style sheet with special importance to Firefox. The rules in userChrome.css are applied to the user interface, and can override nearly every built-in style rule. Unfortunately, you cannot use userChrome.css to change the functional operation of Firefox; that's what extensions are for. Creating a userChrome.css file and adding style rules allows you to make changes to fonts and colors, hide unnecessary items, adjust spacing, and make other changes to the appearance of Firefox. The following examples illustrate the wide range of effects you can create, either by creating your own style recipes, or building on the work of CSS wizards sharing their talents on the web.