refs #14674 - attempts fix for search-filter-toggle SCSS error

themes/bootstrap3/scss/components/offcanvas.scss

@@ -2,10 +2,12 @@ $offcanvas-offset: 80vw !default;  // Width of open menu
 
 .offcanvas-overlay { display: none; }
 
+// Fix you-cannot-extend-from-inside-media-query error:
+// Since .search-filter-toggle is only used on XS devices anyway,
+// we can move the @extend outside the media query -- CK #14674
 .search-filter-toggle {
-  /*@extend .btn;
+  @extend .btn;
   @extend .btn-default;
-  */
   margin-top: 1rem;
   margin-bottom: 1rem;
 }
@@ -24,16 +26,6 @@ $offcanvas-offset: 80vw !default;  // Width of open menu
   }
 
   .offcanvas .close-offcanvas { display: block; }
-  .search-filter-toggle {
-    /* refs #14565 uncommented by vf 5.1 update
-    grunt says that you may not @extend an outer selector from within @media.
-    @to-do fixing bug
-    @extend .btn;
-    @extend .btn-default;
-    */
-    margin-top: 1rem;
-    margin-bottom: 1rem;
-  }
 
   body.offcanvas {
     overflow-x: hidden; /* Prevent scroll on narrow devices */