Fatal error and session destroyed when using dpm in devel/php

Drupal 8 when using devel/php to try to inspect a paragraph in a node, results in the following error, and being logged out of the site.

Failed to start the session in Symfony\Component\HttpFoundation\Session\Storage\NativeSessionStorage

The code I was running was a simple node load and dpm()

$node = node_load(7);
dpm($node);