FireShot

Take screen captures from Firefox

Bookmark Duplicate Detector

Eliminate you duplicate bookmarks from your favorite browser

User Agent Switcher

Tool to switch the user agent used

Autofill Forms

Fill in forms automatically

Web Developer

Toolbar aimed at web programming

WebMail for Thunderbird

Use Thunderbird to manage your webmail

Buffer

Share on social networks the web contents you visit

IE Tab

View websites as if you visited them with Internet Explorer

Shockwave Player

The add-on to play multimedia Flash contents in 3D

Zotero

Complete manager for citations

Sparky Alexa Toolbar

Have Alexa's information in your browser

Lightning

Thunderbird add-on that adds personal organizer functions to the application

TV-FOX

More than 2,500 TV channels live from Firefox

Ank Pixiv Tool

Download manga images from Pixiv

Adblock Plus for Firefox

Block Internet adverts

Foxtana Pro

Have Cortana search Firefox

MediaFire Desktop

Share files with your devices and other users

Filemail

Send large files from your computer

OneDrive

Microsoft's application for cloud storage

SendSpace

Send files to whoever you want

Dropbox

Store all your files on the cloud

MEGAsync

The official MEGA client for PC

Send Anywhere

Quickly and safely send files between devices

MEGA Privacy

Access your MEGA account from Windows

iCloud

Manage all your iPhone's contents

Google Backup and Sync

Backups for your files on Google Drive and Google Photos

TransferNow

Tool to transfer files to different devices

Proton Drive

A secure and private cloud storage service

4shared Desktop

Store your files on the cloud

Google Drive

Google's cloud storage service

Yandex.Disk

Store documents, photos, and videos on the cloud