What cultural faux pas should I try to avoid making in Stuttgart?

"In Stuttgart, punctuality is highly valued, so avoid being late for appointments or meetings. It's considered rude to interrupt someone while they're speaking, so wait for your turn to speak. Avoid discussing World War II or the Holocaust unless it's brought up by someone else, as it's a sensitive topic. Germans value their personal space, so avoid standing too close to someone or touching them unless you're close friends. It's also considered impolite to chew gum or eat in public places like public transportation or while walking on the street. When dining, keep your hands on the table (but not your elbows), and remember to say "Guten Appetit" before you start eating. It's also customary to wait for the host to start eating before you do. In Germany, it's considered impolite to call someone by their first name unless you're invited to do so. Use their last name and the formal "Sie" instead of the informal "du" until you're invited to do otherwise. Avoid making loud noises or speaking loudly in public places, as Germans value quiet and order. Also, jaywalking is frowned upon, so always use pedestrian crossings and obey traffic signals. Lastly, tipping is customary in Germany. While it's not mandatory, it's considered polite to leave a tip of around 10% in restaurants and cafes," remarked another expat in Stuttgart, Germany.