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Open IntelliJ IDEA.
Open Plugins from the Configure menu.
In Marketplace, in the list of plugins, search for “pricefx” to find the plugin named pricefx-studio-<version>.
Click Install.
When the installation is complete, restart IDEA.
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Should you need to install a previous version of Pricefx Studio, refer to https://plugins.jetbrains.com/plugin/19984-pricefx-studio/versions (>= 9.1) or Install Previous Versions (Pricefx Studio) for later ones.