I've only noticed this in a specific case, but it could be happening elsewhere too. When on the add attachment page, I tab through to all the fields instead of clicking around. When I get to the review flags <select> I arrow down to "?" and then tab to the requestee input, autocomplete doesn't attach. It won't attach until after the field is unselected and then focused again (either via tabbing out then back, or clicking out then back)
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