macOs 10.13.6 update
Unfortunately, I was running the security update yesterday as well and there is no Nvidia update available (2020-03-26, 2:30 pm GMT) if you make use of the Nvidia update in the system pane. However, I incremented the last figure of the driver (WebDriver-387.10.10.10.40.134) needed for macOs 10.13.6 (17G11023) to WebDriver-387.10.10.10.40.135 and found this:
Fortunately, the driver does run on my updated system macOS 10.13.6 (17G12034) with Nvidia GeForce 1080Ti!
Since this driver is yet not officially released, please think twice before updating your system!
Hope this will help those who updated their system too quick ... like me