Download 21er

Name: 21er
Author: 21er

By: 21er

Download 21er (current and past versions) for Firefox

Latest Version: 2.0 Updated: 7 years ago Removed

Ready to install?

21er is available for download. Be careful when installing it.

View source code

Available versions

You can find the current and older versions of 21er here. You can download the archived versions or inspect their source codes.

As a free user, you can download up to 3 latest versions.

Upgrade to download older versions

Version	Download	Size	Download count	Timestamp
2.0	XPI · ZIP · Source code	515.38KB	0	2019-05-13

2019-05-13 · 0 downloads

XPI ZIP Source code

Install XPI file

An XPI file, short for "XPInstall," is a compressed file format used primarily by Mozilla applications, like Firefox and Thunderbird, to distribute and install add-ons or extensions. These files are similar in function to CRX files for Chrome but cater to the Mozilla ecosystem.

Simply drag-and-drop the XPI into Firefox to install the add-on.

Install ZIP file

Download the 21er ZIP file.
In Firefox browser, go to about:addons to open Add-ons Manager
Click on ⚙, Install Add-on From File
Select the 21er ZIP file from step 1. 21er is now installed on your browser.