When comparing Opera vs Firefox Developer Edition, the Slant community recommends Firefox Developer Edition for most people. In the question“What are the best browsers for web development?” Firefox Developer Edition is ranked 3rd while Opera is ranked 7th.
Ranked in these QuestionsQuestion Ranking
Pro Built-In Adblocker
The built-In adblocker is faster than any extension. It's possible to add your own filter lists. However, the adblocker isn't enabled by default.
Pro Video pop-out feature
You can pop-out any video and it will stay on top while you are surfing on other tabs.
Pro VPN onboard
Free and fast VPN onboard, includes Germany, Canada, USA, Netherlands, Singapore.
Pro Compatible with Chrome extensions
Since Opera is built on Blink, the same engine Chromium is built on, it was possible for Opera developers to allow Chrome extensions to run in their browser.
Pro Strong HTML5 feature support
Opera scores highly on HTML5 feature support.
Pro Opera Turbo
Opera has a functionality called Turbo which increases browsers speed and reduces data consumption considerably by compressing the data that's found in a web page.
Pro Battery saving mode
Pro You can install extensions on the sidebar
Unlike other browsers, you can install add-ons such as tabs, bookmarks, history, sessions, notes, and extension manager in the sidebar. So you have the flexibility to use it for your purpose.
Pro Opera Sync
Opera Sync allows you to synchronize your bookmarks, passwords, and more from any computer, phone, or tablet.
Opera is full of user controlled settings. Everything can be imported and exported even RSS feeds. It can be skinned in a variety of different themes or it can be extended through the use of a large number of plugins available.
Pro Speed Dial
Opera's Speed Dial (new tab page) has the ability to hold as many websites as you want, and you can customize it almost however you want. You can also organize the websites on the Speed Dial into folders.
You can save the Opera's setup files on a USB hard drive and run its portable version anywhere.
Pro For Opera 2017 & 2018 gonna be time of new
Opera got Reborn UI as the first implementation from Opera Neon concept browser. Snap -feature is next. Opera constantly improves its basic functionality - unlike Chrome.
Pro Partly open source
Source code available on GitHub.
Pro Opera can have extensions from Opera Addons & Chrome Store websites
Opera supports cross-browser extensions. Opera Addons site keeps quality up compared to Chrome Store. Full of useful extensions, Opera also supports extra APIs like Speed Dial API, Extension Sidebar API and Stash API meaning wider variety of extension possibilities than in Chrome.
Pro Blazingly fast
Scores top on Basemark.
Pro Touch bar support
It doesn't consume much RAM, unlike Chrome.
Pro Built-in currency converter
Just highlight price on a website and see this price in your currency.
Pro Fast video loading
Opera loads videos faster, making it useful for slow internet connections.
Pro Ready for work right out-of-the-box
Pro Can be launched alongside Firefox (release version)
Some might find that useless, but that's very practical to dedicate a browser to development.
It's Firefox. It's fast.
Con Cannot select tabs
Unlike in Chrome and Vivaldi, one cannot select multiple tabs to move to another/new window.
Con WebKit/Blink is not customisable or lightweight
Opera is built on WebKit/Blink, which means it shares cons of Chromium: high RAM usage (Not lightweight), lack of customizability.
Con Owned by a Chinese consortium
Who certainly need to conform with Chinese government requirements to let them infiltrate everything you do online.
Con Extension icons not directly moveable
Con Uneditable default search providers
It can not delete or replace already built-in search services such as Yahoo, Google, DuckDuckGo, and Wikipedia.
While Opera is currently available gratis (without monetary charge), it is currently not 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 therefor neither free nor open-source software.
Con Same security-holes as Chrome
Opera 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 Opera.
Con No reader view
Con No address bar in fullscreen mode
Unlike in Vivaldi.
Con Basically a Chrome clone
The latest versions of Opera are basically Chrome clones, so they really don't add anything new.
Some buggy or confusing behavior with the bookmarks bar and moving tabs, and entire windows turning black after a while.
Con Cannot stop auto update
Con Unable to sync extensions
Imagine having 100 extensions and Opera link cannot sync them, which will be troublesome.
Con Needs user prompt to install from Chrome web store
Every time you install an extension, you need to say install first from Opera extension list to proceed.
Con No menu bar
Con Lack of support for source maps in blobs
Still a bit buggy support for CSS source maps coming from blobs. The team is working on it though, and the fixes will eventually land in the production code.
Con May be unstable
Since it is a release channel between beta and Nightly, it may be unstable.