Hi Carol!

Yikes!  I understand the concern.  Here is what I know

When a user enters content in a Rich Content Editor window, the editor automatically saves the content for up to one hour. If the user navigates away from the page or another situation occurs where the user revisits the page within one hour, Canvas will notify the user if any saved content is different from the existing content. The user can preview the autosaved content and select the Yes button to load the autosaved content. Selecting the No button will discard the autosaved content.

This autosave functionality only displays in pages that only include one Rich Content Editor window, such as pages and assignments. Saved content is matched with the page URL and the Rich Content Editor (RCE) ID. For instance, content that is autosaved for an assignment, but never submitted as part of saving an assignment may display as autosaved content when a user returns to the same assignment.

In discussions, autosave is supported when a user is only replying to one thread or comment at a time. Opening Rich Content Editors for multiple replies at the same time (and creating multiple RCE IDs) may not create autosave functionality.

Storage Details

Saved content is stored in each browser’s local storage, which means Canvas can only recover autosaved content using the same browser on the same computer an hour within the last edit.

Additionally, each browser includes a limit for how much information can be saved in local storage, which does not guarantee that the Rich Content Editor will always be able to save a user’s content. 

In the same behavior of clearing a browser cache, users who are able to manage their local storage may want to check and clear their local storage space when using Canvas. Additionally, when manual save functionality is supported, such as in pages, users should frequently save their content; content that cannot be saved as a draft in Canvas, such as assignment and discussion replies, may need to be drafted outside of Canvas to ensure content is not lost.