
I use the following buttons to hide/show various panels:

For my way of working, the circled button should simultaneously hide or show ALL metadata panels subordinated in the View->Info Pane menu item except Preview. Unfortunately it still does not control the Categories metadata pane.
The basic problem is that one cannot dock the Categories Info tab with the other Info tabs inside the Info panel. The following should be possible:

but in 0.69 and prior it isn't possible!

Please make the Categories pane subordinate to the Info Panel!

Some of us dislike the proliferation of so many separate panels and want to "contain" them.
To paraphrase a popular meme: "One panel to contain all the metadata panes, one button to display it."