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

"In Patras, it is considered disrespectful to wave with an open palm, as this gesture is known as "moutza" and is considered an insult. Avoid discussing politics or the country's economic situation, as these topics can be sensitive. It's also considered rude to refuse food or drink when offered by a host, as hospitality is a significant part of Greek culture. When visiting churches or monasteries, dress modestly and avoid wearing shorts or sleeveless tops. It's also important to remember that Greeks value punctuality, but they also have a more relaxed sense of time than some other cultures, so don't be surprised if things run a bit late. Avoid making the "OK" hand gesture (forming a circle with your thumb and index finger), as it is considered vulgar in Greece. Also, remember to respect the local customs and traditions, especially during religious festivals and ceremonies. Lastly, Greeks are proud of their culture and heritage, so avoid making negative comments about their country, history, or culture," mentioned another expat when asked about moving to Patras, Greece.