Add instructions For Media Library Uploads

Question

I want my users to apply a filter in Photoshop every time they upload an image. Naturally, people are forgetful so I want to remind them of that in the Media Library Screen.

I search around which filter/action I could apply to get access to the content but, unfortunately, could not find anything. Is there any direct way to access the "Drop Files" text?

Thank you!

Answer 1

Here are two examples using the pre-upload-ui and post-upload-ui hooks:

add_action( 'pre-upload-ui', function() {  
    ?><h4>
         <?php esc_html_e( 'Please Remember This And That! (pre-upload-ui)', 'wpse' );?>
      </h4>
    <?php 
});

add_action( 'post-upload-ui', function() {  
    ?><h4>
         <?php esc_html_e( 'Please Remember This And That! (post-upload-ui)', 'wpse' );?>
      </h4>
    <?php 
});

You might want to adjust this further to follow the Admin UI style.

This will show up as:

and