Hello same issue here. i have this error on my test "Panther only supports getting normalized text" when running tests." since the symfony 4.4.6 update

I agree. The problem seem to come from this release.
On constraint, they change :
$crawler->text() by $crawler->text(null, false) however in the Panther crawler if you pass false as second parameter, this throw the exception "Panther only supports getting normalized text" :

public function text(string $default = null, bool $normalizeWhitespace = true): string
{
    if (!$normalizeWhitespace) {
        throw new \InvalidArgumentException('Panther only supports getting normalized text.');
    }
    [...]
}

dom-crawler seem to send false as the second argument?

symfony/symfony#35899
symfony/symfony@ff2c362