Well, there are standards for that (RFC 3798 as pointed out above), but this is entirely something in your control so that you can know if an email was read or

Well, there are standards for that (RFC 3798 as pointed out above), but this is entirely something in your control so that you can know if an email was read or not. You choose to turn on tracking (on a per-email basis with a default of your choosing) and then get notified whenever that tracking pixel is hit. And the thought that using Electron and being the best email client are incompatible concepts is misguided. There are many quality products built on top of frustratingly bad technology stacks. But if you think about it, Gmail is a web app too. Different wrapper (your browser), same tech stack. And Gmail is pretty good.