This is not a Canvas issue, but it effected me when I was using Canvas.
This will effect predominately STEM teachers interacting with Canvas through a Chrome web-browser on a MacBook with a touch bar.
Problem: After working for 15 minutes building an assignment in Canvas, suddenly the screen blinks and all my work is obliterated!?!?!
Reason for problem: One feature of the new MacBooks is the "touch bar" at the top. And one feature of the Chrome web-browser is that there is a "reload" key on the touch bar, just above the 3 on the keyboard. If a bit of my finger went above the 3 key when I was typing, it would slightly brush against the reload key on the touch bar. Chrome would reload my Canvas page, thus wiping out my work.
Fix: remove Chrome keys from the touch bar. https://support.google.com/chrome/answer/7570714?hl=en
There's a trick that's clear in the instructions, but that took me a while to figure out. You move your cursor BEYOND the bottom of the screen and you'll see a key in your touch bar becomes highlighted. Click and drag up and it will be removed from the touch bar. I just removed all the Chrome keys from the touch bar to avoid any future problems.
Hope this helps somebody out of a frustrating situation.