iCloud mail stops responding

I am able to log into iCloud normally, and I am able to launch other iCloud apps. When I try to launch iCloud mail, I get an error message that says "Mail has stopped responding."

The steps I've taken so far include the following. Please note that I've taken steps above and beyond what's listed on HT203528:

1: Restarted the browser

2: Restarted the computer

3: Cleared the browser cache

4: Tried the most recent versions of FireFox, Chrome, Opera, Edge, and Safari

5: Tried multiple browsers (starting with Safari) on an updated Mac

6: Tested the issue using multiple networks, including one that was an iPhone personal hotspot

7: Used two separate gateway devices

8: Tested the issue on a brand new computer

9: Sacrificed a goat to Vaal

10: Verified that mail works as expected on my phone and one other computer (The items I need to email are on my primary work computer, and cannot simply be flash driven elsewhere)

11: Verified that the system status is green

The issue has been happening for more than a week.