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Navigating the drop down is possible by using the [Up], [Down], [Home] and [End] keys. Up [Up] and [Down] will highlight the previous or next item in the list, respectively. Home highlight the first item in the list and [End] highlights the last. The drop down will display a maximum of 10 items but you can get to the other items by using the [Up]/[Down] keys. [Home] and [End] only applies to the viewable items in the drop down.
To select an item you can use either [Enter] (or left mouse click) or [Space]. When using [Enter] on a value type item, the cursor will be placed after the closing character of the expression since value types have no children you can get values from. If the type is an object then [Enter] will place the cursor at the end of the selected object's text and before the closing character of the expression. To get the next list of options in the drop down for that object type, press the period key. Alternatively, you can use [Space] to select an item. If the item selected is a value type then the expression will be completed and a space added at the end of the closing character. If the item selected is an object type, [Space] will complete the expression and put the cursor immediately after the closing character.
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