We encrypt files and password protect them for a myriad of reasons. One reason for encrypting files is so that nobody except the intended recipient can access the contents of that file. For encryption, usually we use separate applications such as AXCrypt which is a very good encryption software that offers complete File Explorer integration.
However, when we are in a hurry and do not want to go through a number of applications for encrypting files and then sending them to someone online, we can use the Firefox web browser itself. If we can encrypt or decrypt any file using the browser itself, it becomes very convenient to send the encrypted files online to anyone as we do not have to open any other program for encryption needs.
In Firefox web browser, we are able to encrypt or decrypt files using an extension called File Guard. This extension uses cryptography API (WebCryptoAPI) that is built into the Firefox web browser itself and thus does not require any external files. It uses very strong AES 256 cipher for encrypting the files.
After installing the File Guard extension, we can access it from the browser toolbar. This opens a new window where all the cryptographic features are available. We can select a file for encryption, enter a password for encryption twice and then click on the lock button for encryption. This results in encryption of that file and saving it in the default download folder. Depending on the Firefox download files settings, you can even be prompted with the usual download window.
It appends encrypted extension to the encrypted file which makes for easy identification of these files. The decryption process works in a similar manner. For decryption we have to supply the same password as we used for encryption. This method makes it very convenient to quickly encrypt a document and then email it to someone.
You can download File Guard add-on for Firefox from https://addons.mozilla.org/en-US/firefox/addon/file-guard/.