Button not primary and disabled inside cards doesn't looks like disabled

[ndesorden]

<md-card-actions>
  <md-button disabled>Not looking disabled </md-button>
  <md-button disabled class="md-primary">Yeah, looks disabled</md-button>
</md-card-actions>

This rule overrides the default disabled styles:

.md-card.md-theme-default .md-card-actions .md-button:not(.md-primary):not(.md-accent) {
    color: var(--md-theme-default-text-primary-on-background, rgba(0,0,0,0.87));
}

.md-button.md-theme-default[disabled] {
    color: var(--md-theme-default-disabled-on-background, rgba(0,0,0,0.26));
}

My current dirty fix:

.md-card.md-theme-default .md-card-actions 
.md-button[disabled]:not(.md-primary):not(.md-accent) {
        @extend .md-button.md-theme-default[disabled];
 }