Base64 Converter

This addon provides functionality to convert plain text to Base64 encoding and vice-versa. Similar to the URL Encoder/Decoder, it uses `<textarea>` inputs and buttons. It leverages the browser's built-in `btoa()` (binary to ASCII) and `atob()` (ASCII to binary) functions, which are standard JavaScript APIs designed for this purpose. The conversion happens entirely client-side, making no network requests and operating solely on the provided text string within the browser context.