When you select the Open from device option allows to select while adding a 
Simple Diagrams macro, you can choose any diagram with the .drawio extension stored on your device , insert it into the page and , if necessary, update it using the editor. The uploaded selected diagram will be stored saved in the page’s attachments.
After Clicking the Open from device button click, will open the file manager will be shown.
| Info |
|---|
Note: only files with the .drawio extension |
can be selected, and you can choose only one file at a time. |
After Once you select the diagram is selected and uploaded, a diagram editor opens setting the uploaded diagram as a source.When you have finished working with , it will open in the editor:
Once you've finished working on the diagram, click the Save Save & Exit button to save the your changes and exit the editor or . Alternatively, click Exit to discard the any changes (if made) and leave.
After thatAfterwards, you'll see the a preview of the uploaded diagram.
| Info |
|---|
Note: saving the diagram will update file version in attachments, but won’t raise page version. |