Conditional check to see if a bootstrap.css is included in a theme
You might be able to use wp_style_is() to do this: $style=”bootstrap”; if( ( ! wp_style_is( $style, ‘queue’ ) ) && ( ! wp_style_is( $style, ‘done’ ) ) ) { //queue up your bootstrap wp_enqueue_style( $style, $path_to_bootstrap, $deps, $ver, $media ); } This comes with all the same caveats as @Milo’s solution — it’ll only work … Read more