To reproduce, visit the URL, or try <style> @media all and (min-width:0) { body { } } </style> Result: SHOULD NEVER BE REACHED WebCore/css/CSSPrimitiveValue.cpp(404) : double WebCore::CSSPrimitiveValue::computeLengthDouble(WebCore::RenderStyle *, WebCore::RenderStyle *, double, bool) the primitiveType() is CSS_NUMBER, which is not expected in the switch() statement.
Not sure what’s the right place to fix this. Perhaps the MediaQueryExp constructor, which already does a validity check, should also do feature-specific checks, similar to the CSS parser (using something like CSSParser::validUnit()).
The assertion was added in <http://trac.webkit.org/r95502>, uncovering a preexisting bug.
Created attachment 109416 [details] Make length-comparison media queries accept only length values
Comment on attachment 109416 [details] Make length-comparison media queries accept only length values r=me
Fixed in <http://trac.webkit.org/r96471>.