When the 1px space between menu bar and windows gonna get removed?

Apple doesn’t routinely monitor the discussions. These are mostly user to user discussions.

Send Apple feedback. They won't answer, but at least will know there is a problem. If enough people send feedback, it may get the problem solved sooner.

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Or you can use your Apple ID to register with this site and go the Apple BugReporter. Supposedly you will get an answer if you submit feedback.

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Personally I find it useful. It used to be real hard to have a point to grab on the window. In fact the kiosk view on applications can be disconcerting. Yes Windows likes to put the menubar in every window, but then you have to figure out which window belongs to which program. At least if you do suggest it, make the suggestion include a way to bring it back for those who want it.