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

"It is important to be aware of cultural differences when visiting Macedonia. It is important to be respectful of local customs and traditions, and to dress modestly. Avoid making negative comments about the country or its people, and be aware that public displays of affection are generally frowned upon. It is also important to be aware of the local religious customs, and to avoid eating pork or other non-halal foods in public. Additionally, it is important to be aware of the local language and to avoid speaking English or other foreign languages in public," said another expat in Macedonia.