Description:
------------
It seems that '/^[\\w-:]+$/' is no more a valid regular expression with PHP 7.3: we now have this error

Compilation failed: invalid range in character class at offset 4

I understand that this regex is malformed (I think that the original author of the affected regex may have meant '/^[\\w\\-:]+$/'), but it's a breaking change:
that regular expression worked for all the previous PHP versions (see https://3v4l.org/vD5O2 )



Test script:
---------------
<?php

$tag = 'p';

var_dump(preg_match('/^[\\w-:]+$/', $tag));