In the Custom Dashboard Extension I’ve added this code snippet to fixate 3 columns in the site overview page:
add_filter( 'mainwp_sites_table_features', 'mycustom_fixed_columns', 10, 1 );
function mycustom_fixed_columns( $table_features ) {
$table_features['fixedColumns'] = "{left:3}";
return $table_features;
}
But in the dark theme, these fixed columns stay white, so this styling still needs to be fixed as well.
This is not new in 4.5-beta but already exists since I found this snippet, although I can’t find the link to the source anymore.