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Developer Mode is a standalone version of rFactor 2 which is an option on the when starting rFactor 2 Launcher from the column of icons along the left handside.from your Steam Library. A little menu will pop up and give you the option to either start the main game, run config tool or start Dev Mode.
This is a stripped down install which by default ships with a single location and vehicle. This version also has less restrictions on how files must be packed, to allow for easier development of content. Player files for this version are not shared with the main game. So you will need to configure your settings independently.
Running Developer Mode with the new UI
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Starting via Shortcut
Alternatively you can create a shortcut manually with the following settings:
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