Mozilla's decision to switch the Firefox web browser's extension system to WebExtensions had far-reaching consequences not only for Firefox but also for browsers that share code with Firefox.
I thought it would be a good idea to take a look at the current state of extension support of popular web browsers.
For this, I took a look at the browser's Chrome, Firefox, Edge, Vivaldi, Opera, Pale Moon, SeaMonkey and Waterfox, and what options users of these browsers have to download and install browser extensions.
Note: Mozilla switched to the new extensions system in late 2017. Browsers based on Firefox code may not have transitioned entirely to the new system or a custom system.
The table lists the browsers on the y-axis and the extension systems on the x-axis.
|Browser/Extensions||Chrome||Edge||Firefox **||Opera||Pale Moon|
|Mozilla Firefox||partially *||no||yes||no||no|
|Pale Moon||no||no||no ***||no||yes|
|Waterfox||partially *||no||yes *****||no||no|
* with the help of the Firefox extension Chrome Store Foxified.
** Firefox 57 and newer. Firefox ESR supports legacy add-ons until version 60.
*** Pale Moon supports Firefox legacy add-ons but not Firefox WebExtensions.
**** SeaMonkey supports legacy add-ons only right now. It appears that the developers plan to make the switch to WebExtensions eventually though.
***** Waterfox supports WebExtensions and legacy add-ons currently.
The situation has not changed for Chromium-based browsers or Microsoft Edge. You can separate the extensions landscape loosely into the following groups:
Google Chrome users can install extensions from the official Chrome Web Store. It is a massive store with lots of extensions but also quite a few underlying problems.
Microsoft introduced support for browser extensions in Microsoft Edge in the Windows 10 Anniversary Update. The extension count is very low, however, and it is unclear whether Microsoft is still working on support for Chrome and Firefox WebExtensions.
Firefox users can install browser extensions from Mozilla AMO. This is the main hub for Firefox WebExtensions.
The Firefox add-on Chrome Store Foxified adds a second option however, as it adds support for many Chrome extensions as well. Firefox users may install Chrome extensions from the Chrome Web Store after installing Chrome Store Foxified.
Opera is another special case. Since it is based on Chromium, it does support Google Chrome extensions. Opera Software maintains the Opera add-ons website next to that which is the central Store for extensions for the browser.
Opera users can also download extensions from Google's Chrome Web Store using this extension.
Pale Moon supports Firefox legacy add-ons and add-ons offered on the Pale Moon Add-ons Site. The makers of the browser announced recently that Pale Moon won't support add-ons from Mozilla AMO directly anymore once Firefox ESR reaches version 60.
Mozilla revealed some time ago that it had plans to remove legacy add-ons from AMO after support for these add-ons ends in all Firefox browsers. Pale Moon users can install these add-on manually after the switch is made.
SeaMonkey switched to Firefox ESR recently to buy more development time. The browser supports legacy add-ons only right now.
The Vivaldi browser supports Chrome extensions. Users can head over to the Chrome Store and install browser extensions from the Store directly.
Watefox supports legacy extensions and WebExtensions currently. Users of the browser can download extensions from Mozilla AMO, and they may also use Chrome Store Foxified to download WebExtensions from the Chrome Web Store.
Now You: How important is extensions support for you?
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Ghacks is a technology news blog that was founded in 2005 by Martin Brinkmann. It has since then become one of the most popular tech news sites on the Internet with five authors and regular contributions from freelance writers.