The champions were leading 1-0 through Angel Di Maria's 11th-minute penalty when referee Frank Schneider paused proceedings 22 minutes in.
The fixture was resumed after a little over a minute, once the banner had disappeared out of sight.
It is the second Ligue 1 game this week to be temporarily suspended due to signs displayed in the crowd.
Wednesday's meeting between Nice and Marseille was brought to a halt for close to five minutes while two banners including homophobic language were removed.
Referees in France have been instructed to stop matches if homophobic signs are displayed, or homophobic chanting is heard, during the 2019-20 season.
The Ligue 2 match between Nancy and Le Mans on August 16 was the first to be stopped, while a referee threatened to do the same during the meeting of Monaco and Nimes in the top flight on Sunday.