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Open IntelliJ IDEA.
Open Plugins from the Configure menu.
Click on the Gear Icon to select 'Manage Plugin Repositories'.
Click the 'plus' button to add a new custom repository.
Stable release – https://developer.pricefx.eu/studio/
Latest development Build – https://developer.pricefx.eu/studio/eap (Early Access Program that has the latest features, but it is potentially unstable)
Click OK to close the dialog.
Back in Marketplace, in the list of plugins, search for pricefx to find the plugin named pricefx-studio-idea.
Click 'Install'.
When the installation is complete, restart IDEA.
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