Recs.
Updated
SpecsUpdate
Pros
Pro Ethical and pragmatic company mission
The Mozilla Manifesto outlines the company's mission and principles. Paraphrasing, they want the Internet to be a free and open resource, and to enable individuals to get the best use of that resource. They do this by creating open source software to which anyone may contribute, so long as such contributions fit with their principles (both ethical and technical).
Pro Use very little resources
Firefox 57 (Quantum) and newer uses less resources than ever. It is proven with benchmark done by AppleInsider.
Cons
Con Installing some extensions still requires restarting the browser
While some of the developers already allow users to install their extensions without the need to restart the browser, not all of the extensions have been updated to support non-restart installation yet, as some developers have yet to add special code to do so.
Con Poor performance on SSD even without extensions
On a fast SSD such as Corsair Force LE series this browser still performs as if it were installed on a regular hard drive disk, meaning it takes long time to start, even without any extensions. On that matter Google Chrome is light years ahead of Firefox. This applies only for Firefox versions below 60!
Con Mozilla once partnered with George Soros to fight misinformation
Misinformation can be defined as any opinion in which they do not agree.
Recommendations
Comments
Flagged Pros + Cons
Con Company values politics over good software
They support outright censorship of any opinion they do not share. This is a very dangerous practice because one day it will turn on them and then it will be too late.
Pro Good font rasterizing
Font rasterizing on Windows is much better than in competitors. Even smaller text is clear and contrast.
Pro Uses less resources
Firefox 57 (Quantum) and newer uses less resources than ever. It is proven with benchmark done by AppleInsider.
Pro HTML5 Video Preload
The only web browser that only preloads entire HTML5 video which is useful for slow internet.
Pro Open source
Open Source means that you can see the source code. So everybody even if they don't work for Mozilla is able to look what the browser does in the background. So you can be 100% sure that Firefox doesn't have hidden "spy features" unlike Google Chrome.
Pro Android version allows installation of addons
Unlike other browsers, Mozilla uses almost the same codebase as with the desktop version so extensions work as-is without code modifications - something other browsers cannot do due to their breaking and sometimes unrelated code branches to the mainline desktop branch.