Fastmail is excellent. A bit cheaper than the new Google Workspace and less invasive. It supports multiple domains easily. Interface is great and the iOS app is just as great. I'm sure the Android version is good too.
You have to scroll the browser horizontally for 2000 pixels sometimes, looking at fractions of the image at a time (or download each embedded image and open it in a local viewer to contain it to your screen size).
Fastmail support replied essentially "won't fix".