Selenium IDE-Automating Select2 Search Box
I've had to deal with this as well, the sites I test use select2 and select3. What I've found that works in both situations would be the following:
clickAt | css=.select2-choice > div > b | sendKeys | css=input.select2-input.select2-focused | Chrisclick | css=.select2-result-label:contains('Chris')
With these types of dropdowns, and Angular, I found sendKeys works better than type or typeKeys.
Klendathu