Auto Open a File Preview
In a Canvas text box using the Rich Content Editor (RCE), any link to a file located in the site's Files tool can be automatically opened and displayed to users. This is frequently done in the Syllabus and Assignment tools, but will work in any tool that contains a Canvas text box (Syllabus, Announcements, Assignments, Discussions, Quizzes, Pages)
1. Click on the tool that contains the Canvas text box you want to link the file (Syllabus, Announcements, Assignments, Discussions, Quizzes, Pages) until you reach the Rich Content Editor.
2. Once in the RCE, select the Documents icon  then select a document to upload (Course Documents, User Documents  , or Upload Document .)
This automatically creates a link in the text box to the file.
4. Highlight the link and select Link Options.
5. Select the Preview Inline option and check the Expand Preview by Default box.
6. Click Done.
7. Click Save.