ScrollPane and TitlePane blur text contents including all nested children with text when the pane's layout properties are set to non-Integer value (confirmed cause) and when its parent window is animated (suspicious cause). Other controls such as ListView and TableView with scrolling capability don't have the problem.

The only workaround for ScrollPane I found so far is to revert viewRect.setCache(true) in ScrollPaneSkin. Inside TitlePaneSkin it also calls setCache(true). The cache is not explicitly enabled in all other control skins in 8u20.