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JavaFX is bundled with the JDK as an extension. The jfxrt.jar is located in the extension directory called 'ext' where Java is installed. You must remove it from this directory for the IDE's to work properly. The issue is this: If jfxrt.jar is in the extension directory, it will get seen before the code in your IDE. This means you won't be running or testing anythingthe code in your IDE. For more information on why this is a problem, see Unique Challenges of Working on the JDK.
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