title: How to display a personalized icon for a custom menu in the admin side bar?
body: <p>I'm developing a plugin and I'm a little stuck trying to add a personalized icon to my custom menu in the admin bar.
  I know the basic way to do this is to pass the address of an image file as one of the <strong>add_menu_page</strong> function parameters. I did that and it works, however, the icon is shown a bit "weird" compared to the standard WP admin icons. For example, the colors don't match even after I've edited the .png file a million times. This is specially true for when the mouse hovers the menu (the icon should turn blue, instead it goes white).
  I've read some stuff about this, but nothing conclusive, and I can't find any official documentation about this problem.
  BTW, I tried using an .svg, I think it's even worse!</p>
  
  <p>So, I want to approach this in the most conventional way (I'm guessing there is one) so that I can display my icon properly even if the WP admin theme changes.
  Any thoughts would be greatly appreciated. Thanks in advance.</p>
  
  <p>Here's the code that adds my custom menu page to the admin side bar. It's pretty straightforward:</p>
  
  <pre><code>&lt;?php
  
  public function add_menu_pages() {
      add_menu_page(
          'My Page Title',
          'My Menu Title',
          'manage_options',
          'my-menu-slug',
          'render_my_menu_page',
          PLUGIN_DIR_URL . 'admin/img/my-menu-logo.png', // this is where I call my custom image.
          '26'
      );
  }
  
  add_action('admin_menu', 'add_menu_pages');
  </code></pre>