When comparing Mozilla Firefox vs Vivaldi, the Slant community recommends Mozilla Firefox for most people. In the question“What are the best desktop web browsers?” Mozilla Firefox is ranked 1st while Vivaldi is ranked 3rd. The most important reason people chose Mozilla Firefox is:
Firefox [scores strongly on HTML5 feature support](http://html5test.com/results/desktop.html).
Ranked in these QuestionsQuestion Ranking
Pro Strong HTML5 feature support
Pro Free, open source and community driven
Firefox is available as a free download. All Mozilla software is licensed under the Mozilla Public License. Instructions on how to obtain the source code can be found here.
Pro Syncs between devices
Firefox Sync is an optional feature in Firefox that allows syncing bookmarks, passwords, and add-ons between devices.
Pro Strong developer tool
The built-in developer tools have been merged with the popular FireBug extension since FF57
Pro Reader View
Reader View in Firefox allows users to read an article without any distractions by removing ads, unrelated elements and other distractive objects (similar to Microsoft Edge's Reading Mode and Safari's reader mode).
Pro Uses less resources
Firefox 57 (Quantum) and newer uses less resources than ever. It is proven with benchmark done by AppleInsider.
Pro High performance
The Firefox Quantum update (FF57) greatly increases the render speed and general performance of the browser, by taking better advantage of the user's hardware.
Pro Awesome customizability
Great library of add-ons
Pro Good font rasterizing
Font rasterizing on Windows is much better than in competitors. Even smaller text is clear and contrast.
Pro Tagging bookmarks
Firefox is one of the few browsers that you can tag your bookmarks. You can view a list of tags and can search your bookmarks in the address bar with tags.
Pro Automatically updated
Firefox is automatically updated on the platforms where it makes sense.
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 Fast bookmark management
In order to add an open page to the bookmark bar, the tab can be dragged down and is added immediately.
Pro Lower memory fingerprint than competitors
Firefox used to be a trailer in memory usage, but as of 2017 it's less hungry for memory than competitors like Edge, Chrome, Safari and Opera.
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.
Pro Text-to-speech (with adjustable speed) without add-ons
Firefox Reader Mode includes Narrate, a feature that adds text-to-speech functionality to the browser.
Pro Dark theme
Beyond the toolbar and tabs, it darkens UI elements such as the URL-bar, pop-downs, new-tab page and more
Pro Screenshots tool
Powerful screenshots tool built right into the browser.
Pro Easy screenshots without extensions
Within the browser itself, you can easily take screenshots and save them to your computer.
Pro Integration with Pocket
Firefox comes with built-in Pocket integration that can allow users to quickly save the article for a read it later function to easily find any articles saved in Pocket from various sources and devices.
Pro Amount of AddOns
enormous number of AddOns
Pro Tabs can be stacked
Tabs can be grouped under a single tab to easily keep track of all open webpages.
Pro Compatible with most Chrome extensions
Since Vivaldi is built on Chromium, the same base as Chrome (among other browsers) is built on, it was possible for Vivaldi developers to allow Chrome extensions to run in their browser.
Pro Built for power users
Vivaldi includes lots of niche functionality such as the ability to move tabs to any side of the screen, turn images on and off, or render pages with monospace fonts.
Pro Ability to search through settings, history, open tabs, bookmarks in one place
A feature called Quick Commands (accessed via Ctrl + Q) allows quickly getting to settings, history, open tabs, bookmarks with incremental search.
Pro Full of customizable keyboard shortcuts (can be completely keyboard-driven)
It's possible to change and add keyboard shortcuts for basically all commands. It also has single key shortcuts to execute actions with one click.
Vivaldi is available on Windows, Linux and OSX.
Pro The UI can be customized with ease
Not so easy, hold on guys.
Pro Web Panels
Web Panels allow for easy access to any site from the side panel. They are useful for reading two websites side by side or for chatting (i.e. Facebook) and surfing at the same time. Panels can be hidden when not in use.
Pro Reader mode
Vivaldi has a built-in reader mode so you can remove all the clutter in news pages and read only the content, you can also customise the reader mode, like font size, style and colours.
Pro Analytical history
View graphically the most visited pages on a monthly, weekly, or daily basis.
Pro Mouse gestures
Integrated mouse gestures. Fully configurable as of Vivaldi 1.2 (snapshot available now). Allows for navigating the web, switching tabs, closing windows, opening settings etc. with a flick of the mouse.
A notes panel allows to save notes from webpages and can include screenshots for reference and have tags and organized in folders to help manage them. Thumbnails are too small and Notes do not have separate page in settings, but it should, there are a lot of things to improve.
Pro Tab behaviour can be customised
The order you toggle, open, close or clone tabs can be modified to match a workflow that best works for you. For example you can choose tabs to toggle in recent order so you can go back and forth between the last most useful tabs without needing to change their position on the tab bar.
Pro Cross browser extensions with Opera and Chrome, Firefox web-ext's too
All Vivaldi, Opera and Chrome users can get extensions from all extension/addon sites, especially from Opera Addons and Chrome Store.
Pro Built-in page capture
Vivaldi can grab a picture of the whole webpage or part of it and saves it automatically inside a note or as a file in your disk, or in your elected directory. But I have problems with images of full windows shown on monitor (using X Window System in GNU/Linux). Here I use system XWindow screenshots.
Pro Manages bookmarks well
Vivaldi has an excellent bookmarks system. Bookmarks can be easily accessible via Speed Dial, side-bar, bookmarks bar, quick commands. No more messy bookmarks bar is needed and location bar suggestion is improved thus!
Pro Custom search engines
You can add as many search engines as you like. For example you can set up one for YouTube, one for Wikipedia, or whatever you want: you need only the URL of the search and it can be used from the URL bar (by prefixing it's nickname,
yt for YouTube for example).
Everything can be synced with a Vivaldi account. Though there's still no mobile version you can sync between computers and OSes.
Pro Non-closable fixed tabs
A setting lets you prevent closing fixed tabs so you don't close anything important by accident.
Pro Allows navigating to the next page without searching for the link
A feature called fast forward puts a dedicated button before the address bar that is designed to help you navigate to the next page of a multi-page article, forum thread or search results without having to hunt for the link.
Pro Tab bar position can be changed
Users can change tab bar position to top, bottom left or right
Pro WebRTC IP leaking can be disabled
A built-in setting called "Broadcast IP" will stop the IP leaking with WebRTC when disabled.
Pro VPN is available by extension- also routing through Tor network
VPN and Tor encryption is possible through extensions. Tor is a free choice if one doesn't want to subscribe to a VPN service.
Pro Faster than Firefox or Chrome
Pro Faster than Firefox and Safari
Pro Dark theme out of the box
Pro Saving Sessions
It saves oversights many options and functions implemented in Vivaldi . Eg. see CON "No option to open saved tab stack as... tab stack!"
Pro Updates via dialog box
Unlike most modern browsers (but like most browsers of yesteryear), Vivaldi gives you a dialog box when an new version comes out; it doesn't just update silently in the background. The dialog box tells you about the changes that have been made, and lets you chose when you want to update.
Pro Usable fullscreen mode with address bar when needed
In comparison, on Chrome you will not see the address bar, only on ChromeOS when your mouse is on the top of the screen.
Pro Pioneer of browser features
Presto Opera (Vivaldi's predecessor) is the reason we have a number of common browser features, including tabs and speed dial.
Pro Customizable UI
Vivaldi can change the colors across the browser and has the option to change the color automatically depending on the page. Also, page loading animations are available in the address bar.
Pro Side panel and status bar
Not used fully, they lacks few toggles, that's why I am saying Vivaldi is finished in 80% and unpolished, what makes many people to ditch the browser.
Con When you search in a website (Ctrl + F) there are no marks appearing in the right scrollbar
All Chromium based browsers have this feature.
Con GTK Themes styles the HTML forms
If you're in Linux and you use a dark GTK theme that uses white text and come to a webpage that forces black text on html-forms buttons you will get black buttons with unreadable black text.
Con Uses GTK on Linux/BSD
This makes the integration on non-GTK Desktop Environments very hard.
Con Lack of keyboard shortcuts customization
Keyboard shortcuts can not be changed in a user-friendly way.
It is also difficult to manipulate addons with hotkeys.
Con Installs Addons with updates
Mozilla is installing/integrating addons with every update like the Mr. Robot promotion - it also has integrated Pocket that spams you every time you open the browser or a new tab with partners of Pocket.
Con Some built-in advertising
with their new "pocket" feature, they offer advertisements built-in.
Con Google obsession
Lately, Firefox has been partnering with Google, leading to some privacy concerns.
Con No status bar
There's no status bar. Granted, there is a status tool-tip. But what if you want an actual toolbar, you're out of luck.
Con Can't scroll tabs with mouse wheel
It's pretty basic but you can't switch between tabs back and forth using your mouse wheel. Any add-ons supporting this have been deprecated since FF57.
Con It's a memory hog even though Mozilla claims it is not
Mozilla claims it's using 30% less RAM than Chrome but in real life tests it uses much more.
Con Devtools for WebExtensions are buggy
Con Sometimes buggy
Con Pocket integration
Con Sometimes very buggy and slow
On sites like twitch.tv chat scrolling is still not fixed. Compared to other browsers Firefox is still very slow and feels sluggish.
Con Doesn't care for its original guidelines/goals
Mozilla originally aimed to be the "good guys" with user choice and privacy in mind. Their current leadership cannot be trusted to hold those goals in high regard:
1) Added Pocket - a privacy data sensitive plugin, made it mandatory
2) Tried to sneak in advertisement as "drive-by hack", backpedaled unconvincingly once users complained: https://www.cnet.com/news/mozilla-backpedals-after-mr-robot-firefox-misstep/
3) Tried to randomly inject a small percentage of Firefox downloads in Germany with a data collecting plugin (Cliqz) that tech-savy Germans consider adware (no opt-out question asked) : https://bugzilla.mozilla.org/show_bug.cgi?id=1406647
Con Not available on your Phone/Tablet
Vivaldi is currently only available for desktop operating systems (Windows, Linux, Mac). Though the developers have already said that they plan to release it.
Con Same security-holes as Chrome
Vivaldi uses the same browser engine as Chrome, meaning it has the same security-holes as Chrome. Chrome is a big target for hackers (being the most popular browser in the world), and a webpage that will hack Chrome will also hack Vivaldi.
Con No automatic page translation
Unlike Chrome, it doesn't automatically translate pages that are not in your language.
Con Comes with many Ads
After installation the first thing you have to do is to remove all the default bookmarks and quickdial links which is really annoying. There is more minor stuff like the default search provider or your start page things that could be easily managed with a wizard at the first startup.
Con Can't protect pinned tabs from changing to another URL
Clicking on a page link, then another, easy to wind up far from the original pinned tab site. There is no chrome addon or native vivaldi function to stop this.
Con Extensions miss hotkeys
You can set your shortcuts at vivaldi://extensions, but they do not work.
Con No silent background updates
Unlike most modern browsers, Vivaldi doesn't have the option to update silently in the background. It gives you a dialog box when an update comes out. Worse, the box doesn't warn you that not updating the browser could lead to security risks. That could be pretty bad for your average joe, who doesn't know computers that well.
Con No guarantee that you won't lose your session
The browser window may freeze at any time, and you lose all your progress, open windows, and session without an option to restore it next time you open your browser.
Con No option to open saved tab stack as... tab stack!
You may save stack, but you can open it as separate tabs. Interesting that when you save session with stacks, you'll be able to open the stacks with inner settings of page tiling (size and zoom) as well. Contradiction worth of shame.
Con No touch bar support
While Vivaldi is currently available gratis (without monetary charge), it is currently not fully libre (meaning that it does not allow users to view the source code used to create, to modify that code, or to redistribute modifications) and is therefore neither free nor open-source software.
The C++ source code however is open-source under a BSD license and can be downloaded and browsed from here.
The UI code though is not open-source, but it's easily readable as it's HTML, CSS & JS. Modifications can be shared as their forum even has a dedicated section.
Con No built-in proxy
Unlike Opera (but like most browsers), Vivaldi doesn't have a proxy service out of the box. You'll need an extension or an external program, to use Vivaldi with a proxy server.