Features I wish paint.js had

[Pager07]

trafficstars

1. Be abel to have infinite space to draw or alteast be able to extent it the size of canvas
2. Has a easier access to swap between different stored images.
3. Be able to sync the image to google drive. ( I keep running out space in chorme, so I often have delete all stored image)

[1j01]

1. I agree an infinite canvas would be cool. You can resize the canvas tho, either with the handles at the corners, or by specifying a document size in Image > Attributes.
2. You can open multiple tabs of jspaint.app and open different images in them, if you want to switch back and forth between documents frequently. Or if you want to switch between multiple files on your computer quickly, in one jspaint instance, you could open the file browser and position it beside the web browser window with jspaint and drag and drop files in to edit. (~~Warning: opening files currently overwrites the session (stored image) instead of creating a new session.~~)
3. See https://github.com/1j01/jspaint/pull/143 - with Native File System support, you could use a local Google Drive / Backup and Sync client and just edit files in the local Google Drive folder on your computer (as well as other places, and other services like Dropbox)