I tried to set the following parameter to false. By the way - the default is true
Link back to Media Module from Theodul player (true|false)
# Default: false
prop.link_mediamodule=false
The logo content in the upper right side of the player was not longer available.
When I clicked on the button I was redirected to https://opencast-dev.uni-koeln.de/engage/theodul/ui/false.