\documentclass{article}

\begin{document}

This is a long line with a unicode arrow in the middle of it ↓ which should be split correctly

Here an indent begins (
and should not be closed with this arrow and comment ↓%
until the next parenthesis
)

This line contains some French accent characters éééééééééééééééééééééééééééééé
which include zero-width chars, so look narrower than they are.

\end{document}
