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Playing movies
The MegaSuperAwsomeQuickTimePLayer (MSAQT Player) is a simple programme for playing endless loop of video fullscreen.
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System Settings> Users & Groups> Select Users> Login Objects> Objects that are dragged into the window are automatically opened at startup
Automator
Sometimes you might need to do something more complicated that just starting a programme. Perhaps you need to open applications in a particular order, or even use some key shortcuts to start a serial connection or enter presentation mode. Automator is easy to use, comes preinstalled on IOS. The example below opens two applications, then some applescript runs some keyboard shortcuts, and even hides the mouse pointer. Automator can also export this workflows into an application, which can be selected to run on startup (see instructions above)
Important! if if you export an automotor application running applescript, you will need to allow it the application access to control your computer.
After saving (and after every time you makes changes!): System Settings> Security and Privacy > Privacy > Accessibility > Drag and Drop your Automator application here.
Marcopolo
Sometimes you need to do something a little more complicated, for example only run a fullscreen application only after a beamer or external monitor is turned on, or when a particular usb device is connected. Marcopolo allows "context-aware computing" and is quite easy to use.
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