This issue affects only the ruby-sass implementation which is deprecated.
Use node-sass or sassc instead.
Sass lets you easily specify multiple selectors at once like this:
.some-block
  &.has-hover,
  &:hover
    outline: 1px solid red
This will add a red outline on either real hover or when the has-hover class is present. However, adding a comment will void the definition of that line:
.some-block
  &.has-hover, // From hoverable.js <-- DON'T
  &:hover
    outline: 1px solid red
... will simply drop the &.has-hover part in 
  ruby-sass
  
    Show archive.org snapshot
  
(deprecated). 
  sassc
  
    Show archive.org snapshot
  
 and 
  Node Sass
  
    Show archive.org snapshot
  
 (Dart Sass transpiled to JS) are not affected by this problem.
Posted by Dominik Schöler to makandra dev (2017-04-25 10:02)