Chrome Version: 73
OS: Chrome

What steps will reproduce the problem?
(1) enable autocomplete
(2) type "toas"
(3) witness "toaster" be autocompleted
(4) press backspace, then enter

What is the expected result?
"ter" is deleted, "toas" is searched

What happens instead?
in spite of the text "toas" being in the field, "toaster" is searched instead. You must press "down" several times before gaining access to the ability to search your query.