Hi Daniel,
Thank you for contacting Syncfusion Support.
We have checked the reported query and by default SfDockingManager will not be in Transparent view. We have prepared a sample and video for your reference and it can be downloaded from the following link.
Note:
SfDockingManager gets transparent background only when we set the Background property as Transparent.
Please check the above video and confirm us whether we followed your replication steps or not. Please provide more details about your problem like code settings which would be helpful for us to proceed further on this.
Regards,
Arulraj A