Ortur has refused to publish the modified source code of their grbl based firmware after two requests. Now that my personal escalation level 3 is reached, here is the video:

For those of you, that like to put more pressure on Ortur by demonstrating that more people have an eye on their wrongdoing, the support email is:

support@ortur.tech

Ask politely to get the source code by pointing to their use of grbl and the GPL v3 license text - thanks!