(I customize the Dock using other means, so the hidden menubar was my only interest) So if you depend heavily on Spotlight, count this feature out if you're wanting to use Docker. Perhaps a workable solution for an occasional spotlight user, but for someone that uses it constantly as the OS X keyboard accessible launcher, that absolutely cripples functionality and workflow.
The developer knows about the issue and suggested leaving the menubar visible in the finder, and clicking to the finder when spotlight is needed. Would have saved me the hour I spent, first manually changing the setting for every single regularly used app in my folder, and then immediately having to undo it all one by one after I realized losing spotlight was the price I payed for a bit of clear screen.
I'm frustrated that there is no mention of this known issue anywhere on the site or in the documentation. both from keyboard shortcut access and even mouse triggered access.
You need to manually change the setting for each application you want to have a hidden menubar for AND once the menubar is hidden spotlight is disabled. It works, but there's an unfortunate sacrifice. Installed this specifically for the menubar hiding feature.