Please update scssphp to v0.8.4 (or even better; v1.1.1)

@remgronl

If you need v1.1.1, you can still just replace the scssphp folder with the newer version of ScssPhp, but you have to do 2 more steps within the plugin itself:

1. bulk update the new namespace change in the WP-SCSS plugin:

Replace ALL occurrences of Leafo\ScssPhp with ScssPhp\ScssPhp

(currently, it should be 9 occurrences in 3 files:

wp-content/plugins/wp-scss/options.php
wp-content/plugins/wp-scss/wp-scss.php
wp-content/plugins/wp-scss/class/class-wp-scss.php

2. update the namespace stored in options as the compile option

And as a quick hotfix in
wp-content/plugins/wp-scss/wp-scss.php

after this line (probably around line 115):

$wpscss_options = get_option( 'wpscss_options' );

insert this:

// TMP HOTFIX
$wpscss_options['compiling_options'] = str_replace('Leafo\ScssPhp\Formatter', 'ScssPhp\ScssPhp\Formatter', $wpscss_options['compiling_options']);

(Proper fix would be replacing the option in DB which I was not able to find quickly, but this works ?? )