13075 2011-06-28 09:09:52 +0000 Vendor Extensions as warning not available in help or as argument. 2011-06-28 09:09:52 +0000 1 1 1 Unclassified CSSValidator Other CSS Validator Macintosh MacOS X NEW P2 normal --- 1 stefan.w dave.null www-validator-cvs oldest_to_newest 50395 0 stefan.w 2011-06-28 09:09:52 +0000 From digging around in the source code it looks lite it should be possible to invoke the validator warning and not throwing errors for the vendor extensions by feeding it this line of code: java -jar css-validator.jar --vextwarning=true http://url And it doesn't choke on the argument. But these to lines produce no different output: # java -jar css-validator.jar --vextwarning=true --output=xhtml http://url # java -jar css-validator.jar --vextwarning=false --output=xhtml http://url Further on it is not visible or documented in: java -jar css-validator.jar --help