Emoji autocomplete popup should trigger only after more than one character has been typed

[FlameFractal]

Motivation It's impossible to use old school emoticons (for eg. :) or :P) in the chat. If I type :P and press enter, because it would get sent as 📦, which is the first result in the autocomplete emoji search.

Proposed solution We should replace, or even show the autocomplete emoji search popup only when more than one character is typed after the trigger (:) colon. Slack (on desktop macos app) also does the same.