Email tracking extensions opening backdoor for tracking

[trockerapp]

Some email tracking extensions subvert blocking by opening tracking images in their background page. We are not aware of any solution that Trocker could implement to stop this because it seems that extensions cannot block requests from another extension's background page. So, let's make a list of those tracking services that do this so that Trocker users who experience a blocking failure can confirm if they a are using a tracking extension that causes it.

To check if an extension is enabling tracking from its background page, you can do the follwing:

1. Open the extension's background page from the details page for that extension from Chrome's extensions page.
2. Open the network tab so that you can monitor the network requests from the background page.
3. From another browser tab, open an email that you know is tracked and seems to not be blocked by Trocker. If the background page makes netwrok requests at the same time as when you open the email, those requests are likely to be the same tracking images being loaded from the background page to enable tracking. You can confirm this by checking their url in the network tab and comparing it with the tracking images in the email source.

Please feel free to report your findings about services that do this as comments.

[trockerapp]

Article about this: https://medium.com/@trockerapp/how-you-may-be-inviting-spies-into-your-emails-3e89dc5ce2e9