I give up! I tried everything I could think of to put the embedded (in an #iframe) #vhx / #VimeoOTT video player in #fullscreen #programatically (without a click or keypress) in a #userscript via #FireMonkey and either the script is blocked by #CORS or the fullscreen request fails or nothing happens.
I have tried adding the script to the website (www.dropout.tv), to the iframe (embed.vhx.tv with @allFrames), using the player API or vanilla JavaScript, directly in the userscript or by appending a <script> element.
The furthest I got was running the focus() method of the iframe so I can press "f" without having to click on the player first.