See the attached example. Inside a markup element, dismiss any displayed intellisense list with Esc. Press Ctrl+Space to get a list of items. The VS intellisense list is displayed. Now enter a single character (E.G. b) and press Ctrl+Space to get a list of items. The R# intellisense list of 'b' items is displayed. Now press the backspace key which causes R# to display all items in the list. Press Ctrl+Space again and notice that the VS intellisense list pops-up behind the R# list and the VS list has the input focus. Navigating using the Up or Down arrow keys navigates through the VS list, not the R# list. In all of these cases, R# should display its own intellisense and prevent VS intellisense window from displaying.