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- Are you using MIT App Inventor Classic, MIT App Inventor 2, or something else (what?)
- What OS are you using? (e.g, MacOS 1.8, Windows 8, ...)
- What browser are you using (e.g, Chrome version 30, Firefox 24, IE 8, ...)
Also provide as much information as you can, such as screenshots and instructions that will let others duplicate the issue.