When I update Elementor and PhLox pro plugin my website breaks

I'm quite new to WordPress development since I hate being attached to plugin compatibilities and updates that break everything.

I have a client with a wordpress site which is completely out of date (wordpress 5.x, php 7.2, all plugins more than 5 versions older than they should).

So far, I managed to download the site locally and set it up to check that updates don't break anything, and I did not have much trouble updating wordpress and most of the plugins except for...you guessed it...Elementor and related plugins (PhLox). Apparently upgrading Elementor is not the problem, but PhLox is.

When I update Elementor (and Elementor pro), my site shows up blank, and when I check PHP log, it says PHP Fatal error: Uncaught Error: Class 'Elementor\Scheme_Typography' not found in D:\wamp64\www\..., which is due to PhLox not being updated. Now, the obvious thing to do would be to update PhLox, and that's what I tried to do, but doing that I ended up having another error PHP Fatal error: Uncaught Error: Call to undefined function auxin_kses() in D:\wamp64\www\....

There seems to be no answer from PhLox community regarding this error, so I'm not sure what to do. Any idea?

After several hours of research, I only found one possible solution (which is only half a solution).

My site was not working with every plugin updated and the problem was apparently comming from PhLox which has little to no support apparently (Shame on them). I decided to try to keep the old PhLox version and just solve compatibility issues with new Elementor version. It turns out, the only broken thing was a reference to old Elementor\Scheme_Typography which is now Elementor\Core\Schemes\Typography. So the solution is:

1. Either replace all references to Elementor\Scheme_Typography to Elementor\Core\Schemes\Typography
2. Or Create a folder under wp-content named mu-plugins and place inside a php script named (for instance) phlox-fix.php with the following code:

<?php
/**
 * Plugin Name: Elementor Scheme_Color and Scheme_Typography Class Issue
 **/
namespace Elementor;
\add_action(
  'plugins_loaded',
  function() {
    if ( ! class_exists( 'Elementor\Scheme_Color' ) ) {
      class Scheme_Color extends Core\Schemes\Color {}
    }
  }
);
\add_action(
  'plugins_loaded',
  function() {
    if ( ! class_exists( 'Elementor\Scheme_Typography' ) ) {
      class Scheme_Typography extends Core\Schemes\Typography {}
    }
  }
);
?>

That's what worked for me and now I have a "less-outdated" site which cannot run yet with versions of php higher than 7.x.x due to PhLox not being updated -.-'

Hope it helps someone