When working in the Canvas Rich Content Editor (RCE), users who are still composing answers should be careful to not navigate away from the page with their browser back button, or have the same Canvas assignment or test open in two separate browser tabs. (This happens more often than you might think!)
The below information is provided by Canvas from their Help article How Do I Add and Modify Text in the Rich Content Editor as a Student. More information about the limited autosave feature is towards the bottom of that article.
If you reload or navigate away from a page while editing content in the Rich Content Editor as a student, Canvas automatically saves your content in the browser cache for up to one day. When you reload the page or navigate back to the page you were editing, Canvas displays a message indicating that auto-saved content exists. You can preview the content, discard the content, or load the content into the Rich Content Editor.
Notes:
- Auto-saved content is not a guaranteed feature and may not save content in certain situations.
- The amount of local storage available may vary depending on which browser you use.
- Auto-saved content is only available on pages that only include one Rich Content Editor window.
- Auto-saved content is only available in the same browser and computer you were using when you created the original content.