MageTools is a privacy-focused extension by design.
The only time we collect personally identifiable information is during the (optional) license payment flow, which takes place via Gumroad.
MageTools can't access any page until you open it. Once you leave (or refresh) the page, it loses access. This design is intentional to make sure that MageTools only runs when you want it to. In Chrome's words, it uses "no special permissions".
The only permissions we request in the extension's manifest.json, as well as the reasons for using them, are:
activeTab: This allows MageTools to run on the active page after you explicitly invoke it. It is the most privacy-friendly way to let MageTools work.
storage: Some people use MageTools across multiple computers. This permission allows the license key to sync between computers where you're signed into the same Google account, which is a better UX (so you don't need to enter your license key multiple times) and fairer than incrementing your license key for each machine.
contextMenus: This allows you to right click and select "Toggle MageTools" from the context menu.
If there's any way to make MageTools more privacy-friendly without degrading the core experience, please open an issue on GitHub with recommendations.
This policy is effective as of 26 September 2020.