KeePassX: password manager or safe which helps you to manage your passwords in a secure way. You can put all your passwords in one database, which is locked with one master key or a key-disk. So you only have to remember one single master password or insert the key-disk to unlock the whole database. The databases are encrypted using the algorithms AES or Twofish.
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AdBlocker Ultimate
Free and improved AdBlocker. Completely remove ALL ads. No "acceptable" ads or whitelisted advertisers, block tracking and malware!
Cookie Quick Manager
A complete manager for cookies accumulated during browsing. It allows you to view, edit, create, delete, backup, restore cookies and search them by domain names. Contextual Identities such as Private Browsing, First-Party Isolation, and SameSite flag are also supported.
Disconnect
Make the web faster, more private, and more secure. Visualize and block the otherwise invisible websites that track your search and browsing history.
Flagfox
An extension that displays a flag icon indicating the current webserver's physical location. Knowing where you're connected to adds an extra layer of awareness to your browsing and can be useful to indicate the native languages and legal jurisdictions that may apply. Additional information can be obtained via a multitude of external lookups and users can add their own custom actions. All actions can be added to the flag icon's context menu and set to icon click or keyboard shortcuts for quick access.
FoxyProxy Standard
Easy to use advanced Proxy Management tool for everyone.
I2P In Private Browsing
This is an Experimental webextension which introduces a set of new "Private Browsing" modes to Firefox-based browsers(Supporting webextensions) that makes it easier to configure a browser to use I2P securely and adds features for making I2P applications easier to use. It does this by isolating I2P-specific settings to Contextual Identities within Firefox, then loading them automatically when the user requests them. It also adds convenience and management features specific to I2P like protocol handlers and native messaging systems.
NoScript Security Suite
Maximum protection for your browser: NoScript allows active content only for trusted domains of your choice to prevent exploitation.
Plasma Integration
Multitask efficiently by controlling browser functions from the Plasma desktop.
Smart HTTPS
Helps you always use the secure HTTPS protocol, if supported by the site’s server. It automatically changes HTTP protocol to the secure HTTPS, and if loading errors occur, the extension will revert back to the original HTTP protocol.
User Agent Switcher
A highly customizable extension to spoof the User-Agent string of your browser with a new one globally, randomly or per hostname. You can alter your user-agent string to indicate you’re on a mobile device if you prefer seeing mobile versions of sites so they load quicker.