Servo 0.4.0 contains all of the changes we landed in June, which came out to yet another record 558 commits (April: 534, May: 391). For security fixes, see § Security . We’ve shipped several new web platform features: ‘attr()’ , in experimental mode ( @Loirooriol , #45041 ) ‘image(<color>)’ , ‘closest-corner’ , and ‘farthest-corner’ in ‘ellipse()’ and ‘circle()’ ( @Loirooriol , #45421 ) ‘calc()’ and other mathematical expressions can now be resolved later than parse time, e.g. sign(1em - 32px) ( @Loirooriol , #45421 ) ‘font-feature-settings’ in ‘@font-face’ ( @simonwuelker , #45393 ) ‘@media (device-width)’ , ‘@media (device-height)’ , ‘@media (height)’ , ‘@media (aspect-ratio)’ , and their min- and max- variants ( @jdm , @mrobinson , @nicoburns , @jschwe , #44978 , #45707 , #45490 ) ‘@media (orientation)’ ( @nicoburns , #45707 ) ‘@media (pointer)’ and ‘@media (any-pointer)’ ( @nicoburns , #45681 ) ‘@media (hover)’ and ‘@media (any-hover)’ ( @nicoburns , #45681 ) Plus a bunch of new DOM APIs:…