Hello @dylan I apologize for the inconvenience this is causing, let me share some resources for you to check and do some troubleshooting to check if it will solve the problem.
A possible solution to your blank Canvas to-do list is to clear your browser's cache and cookies. Although you've tried different browsers, a common issue with web applications like Canvas is corrupted or outdated data stored locally. Since the issue is happening across multiple browsers, it's less likely to be a simple cache problem, but it's the easiest and most common fix to try first.
(Check these resources from the Community page)
1. To do list problem
2. Canvas is blank
I hope this helps. Thanks!