I get many \"Unknown property\" warnings in my css files.
This might be due to the fact that I have e(fx)clipse 2.0 and the Eclipse Web Developer Tools installed. <
I filed an e(fx)clipse bug [1] and uninstalled e(fx)clipse for the time being.
The main reason why I had installed e(fx)clipse at the beginning was to get rid of the access restriction warnings related to jfxrt.jar (also see [2]). Now I use additonal access rules for the JRE container in my classpath file instead of using e(fx)eclipse:
[1] https://bugs.eclipse.org/bugs/show_bug.cgi?id=475347
[2] Using JavaFX in JRE 8