False positive for table headers when extra whitespace is present

[bagofarms]

Indiana University has reported false positives for tables that already have headings caused by empty spaces being seen as child nodes by libxml, specifically evident when checking for tags as first child of tags as in quail’s accessibility_tests.php

I have not been able to replicate the issue so far, but I have inquired about example code.

Erik Scull from IU recommends placing the following code after $this->prepareValue(); in:
https://github.com/ucfopen/UDOIT/blob/master/lib/quail/quail/quail.php#L165

function prepareDOM()
	{
		$this->prepareValue();
		$this->is_valid = @$this->dom->loadHTML('<?xml encoding="utf-8" ?>' . $this->value);
		$this->prepareBaseUrl($this->value, $this->type);
	}

$this->value = preg_replace("/\>\s+\</m", "><", $this->value);