I noticed that when I run JavaFX application on JVM 7 and JVM 8 I get different default skins. How I can set the default skin to be same on every JVM?
You can set your own skin by adding a style sheet.
scene.getStylesheets().add( getClass().getResource("my-skin.css").toExternalForm());
Unfortunately there is no default style sheet. Maybe browsing in jfxrt.jar might yield something.