When the styles and formatting dialog was independent from the sidebar in 4.3, when pressing F11 the dialog appeared and when pressing F11 again, it would hide. In 4.4+, pressing F11 opens styles and formatting in the docked sidebar and pressing F11 again, hides it in the sidebar. But if the sidebar is undocked and you press F11 when on the styles and formatting tab, it doesnt hide the floating sidebar.
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