Print Edit WE uses the new Firefox WebExtensions API's, which are the same as the Chrome extension API's.

These API's do not allow extensions to perform certain types of operations on a few pages, which are either browser administration pages or web store pages, specifically:

- about:
- moz-extension:
- https://addons.mozilla.org

- chrome:
- chrome-extension:
- https://chrome.google.com/webstore