JavaScript Toggle On and Off is a Firefox add-on designed for web developers and users who need precise control over JavaScript execution. This subscription-based WebExtension allows users to disable JavaScript in both standard and private browsing modes with ease. After installation, JavaScript execution is enabled by default, and users can quickly toggle it off by clicking the toolbar button or using the default hotkey 'Alt + Shift + L'. The add-on also features domain whitelisting, enhancing its usability and flexibility for specific sites.

This extension effectively manages various types of JavaScript, including inline scripts, data URIs, external scripts, inline events, and more. While it is noted that this version may be slightly less powerful than previous iterations, it remains a reliable tool for anyone looking to control their browsing experience. Users can check their browser's JavaScript support through integrated tools and report any issues via GitHub.