Select: optimize performance of long option list (#4444)

packages/select/src/option.vue

@@ -6,8 +6,7 @@
     v-show="visible"
     :class="{
       'selected': itemSelected,
-      'is-disabled': disabled || groupDisabled || limitReached,
-      'hover': parent.hoverIndex === index
+      'is-disabled': disabled || groupDisabled || limitReached
     }">
     <slot>
       <span>{{ currentLabel }}</span>

packages/theme-default/src/option.css

@@ -26,7 +26,7 @@
         }
       }
 
-      &.hover {
+      &.hover, &:hover {
         background-color: var(--select-option-hover-background);
       }