It's not just the waves effect, it seems everything isn't properly initialised. After a reload of the page everything works fine.

Unfortunately not. Generally, the wave effect is added when the MDB scripts are loaded. It seems that in this case the scripts are loaded first, then the cache.

The only solution is to manually add a wave effect by adding code that runs automatically when the page loads:

$(document).ready(function () {
  //Initialization
  Waves.attach('.btn:not(.btn-flat), .btn-floating', ['waves-light']);
  Waves.attach('.btn-flat');
  Waves.attach('.chip');
  Waves.attach('.view a .mask', ['waves-light']);
  Waves.attach('.waves-light', ['waves-light']);
  Waves.attach('.navbar-nav a:not(.navbar-brand), .nav-icons li a, .nav-tabs .nav-item:not(.dropdown)', ['waves-light']);
  Waves.attach('.pager li a', ['waves-light']);
  Waves.attach('.pagination .page-item .page-link');
  Waves.init();
});

However, I am afraid that this will cause a duplication of the effect on elements where the waves were correctly added after the page was loaded. The effect will be that the wave will appear darker on these elements. In fact, it will be two waves.