The proprietary email client listed under Privacy Guides’s recommendations for email client called Canary Mail emailed me some spam about them having “read reciepts”
I wasn’t aware of that. Thanks for letting me know.
I’m not sure why I didn’t already Google it, probably because I’m tired and it’s 10pm and i just got home from work but I did find an article that says yes they do infact use tracking images Email Read Receipts: Who's Reading Your Emails? | Canary Email