Follow-Ups

Follow-up plugin automatically adds a tracking pixel to each sent email. It basically tracks as soon as someone is opening the email.

This is not allowed according to the working party on the protection of individuals with regard to the processing of personal data in the EU unless you have gotten explicit consent to actually track their email usage. This consent needs to be informed, specific, etc meaning a user must be made aware eg at the time of purchase that you will be tracking their email opening. Mentioning this in the privacy policy under legitimate interest might not be enough.

This means, by default, anyone using this plugin who sends emails to eg EU citizens is at risk of facing fines.

You can read more about this in https://ec.europa.eu/justice/article-29/documentation/opinion-recommendation/files/2006/wp118_en.pdf in the section “V. OTHER EMAIL RELATED SERVICES”.

There is a workaround to remove the filter that is adding the tracking pixel. However, it can easily break at any time should the filter be changed in any way.

I suggest you add a feature to disable this tracking pixel and maybe even have it disabled by default so people have a chance to check their legal situation, privacy notices and privacy policies before opting in to this.

Another downside is that some email providers are smart and detect tracking pixels meaning such mails are more likely to be classified as unimportant or may be even put into spam.