Unless they were looking, they wont have seen it. And as far as I know, just the cursor being active sends the “typing” indicator in some apps. When I see it for just a second I just assume someone hovered over the chatbox for a bit.

No-one thinks it’s wierd for it to pop up for a second and then go away.

It would be smart if chat apps implemented a minimum, where “typing” won’t apper until you’re three words into writing a response or something.

That way it wont go off over nothing. It’s still useful, it lets you/them know whether you’re getting/giving an immediate response, so you/they know whether the conversion is continuing right away, or later.