Single Click To Expand in Grouped/Non Flattened ValueDropDownList

[Richard Baxter]

Having to click -> select -> click -> expand feels like the dropdown list feels like it's laggy (it's not, but most of my team expects it to work on one click and finds it 'laggy', or like it's not working properly).

Would really like to have an open to select and expand in one click, rather than select then expand, which takes two or a double click.

Could be combined maybe with the https://bitbucket.org/sirenix/odin-inspector/issues/390/valuedropdownlist-search-options-for suggestions