Don't use Enter key to autocomplete insertion in text

Love the new feature about markdown and emoji previewing directly in typebar.

Something I noticed: Tab is used to autocomplete names like emojis or mentions etc. and Enter as well. Maybe Enter might be used only to send the message.

This would avoid sending the message by accident when trying to autocomplete at the wrong time, and mostly avoid having to press Enter twice to send a message ending with a (complete or not) mention, like the complete `:emoji:` string.