sealed and abstract are not highlighted when used as class/trait modifiers

[slothspot]

In code example like following:
sealed trait List[+A]
sealed modifier is not highlighted.

Same for:
abstract class T { ... }

Quick workaround, which looks incorrect, is to link scalaKeywordModifier to Keyword:
hi link scalaKeywordModifier Keyword

But I suppose that correct solution to problem is to move abstract, sealed to separate modifiers group