Input lines lost if updated very fast

[ehhov]

Overview

If input lines come too close to each other in time, some of them may be lost and never printed.

Steps to reproduce

Run

{ for line in 'first line' 'second line' 'third line'; do
        echo $line
        sleep .01
done; sleep 1; } | umess

One might need to reduce the intermediate sleep time or remove it altogether to see the effect.

Possible solution

When the input read from stdin contains multiple lines, use the last one instead of the first one.