We do observe this issue with the SB. I am trying to reproduce outside of SB but this bug seems tightly related to our CSS structure and containment.

The output:

WARNING: com.sun.javafx.css.StyleHelper calculateValue Could not resolve 'scrollbars-base' while resolving lookups for '-fx-background-color' from rule '*.scroll-pane>*>*.scroll-bar:vertical' in stylesheet file:/Users/jfdenise/workspaces/scenebuilder/authoringtool/AuthoringTool/build/classes/com/oracle/javafx/authoring/css_stylesheets/ContentView.css
WARNING: com.sun.javafx.css.StyleHelper calculateValue Could not resolve '-fx-box-border' while resolving lookups for '-fx-background-color' from rule '*.scroll-bar:vertical *.track-background' in stylesheet jar:file:/Users/jfdenise/workspaces/scenebuilder/authoringtool/authoringtoolBinaries/sdk/rt/lib/jfxrt.jar!/com/sun/javafx/scene/control/skin/caspian/caspian.bss
WARNING: com.sun.javafx.css.StyleHelper calculateValue Could not resolve 'scrollbars-base' while resolving lookups for '-fx-background-color' from rule '*.scroll-bar *.thumb' in stylesheet file:/Users/jfdenise/workspaces/scenebuilder/authoringtool/AuthoringTool/build/classes/com/oracle/javafx/authoring/css_stylesheets/ContentView.css
WARNING: com.sun.javafx.css.StyleHelper calculateValue Could not resolve 'scrollbars-base' while resolving lookups for '-fx-background-color' from rule '*.scroll-pane>*>*.scroll-bar:horizontal' in stylesheet file:/Users/jfdenise/workspaces/scenebuilder/authoringtool/AuthoringTool/build/classes/com/oracle/javafx/authoring/css_stylesheets/ContentView.css
WARNING: com.sun.javafx.css.StyleHelper calculateValue Could not resolve '-fx-box-border' while resolving lookups for '-fx-background-color' from rule '*.scroll-bar:horizontal *.track-background' in stylesheet jar:file:/Users/jfdenise/workspaces/scenebuilder/authoringtool/authoringtoolBinaries/sdk/rt/lib/jfxrt.jar!/com/sun/javafx/scene/control/skin/caspian/caspian.bss
WARNING: com.sun.javafx.css.StyleHelper calculateValue Could not resolve 'scrollbars-base' while resolving lookups for '-fx-background-color' from rule '*.scroll-bar *.thumb' in stylesheet file:/Users/jfdenise/workspaces/scenebuilder/authoringtool/AuthoringTool/build/classes/com/oracle/javafx/authoring/css_stylesheets/ContentView.css
WARNING: com.sun.javafx.css.StyleHelper calculateValue Could not resolve 'scrollbars-base' while resolving lookups for '-fx-background-color' from rule '*.corner' in stylesheet file:/Users/jfdenise/workspaces/scenebuilder/authoringtool/AuthoringTool/build/classes/com/oracle/javafx/authoring/css_stylesheets/ContentView.css