KUALA LUMPUR, June 23 (Reuters) – Malaysia said on Friday it will take legal action against Facebook parent company Meta Platforms (META.O) for failing to remove "undesirable" posts, the strongest measure the country has taken to date over such content. Last year's closely fought national election has led to a rise in ethnic tensions and since coming to power in November, Prime Minister Anwar Ibrahim's administration has vowed to curb what it calls provocative posts that touch on race and religion. Facebook has recently been "plagued by" a significant volume of undesirable content relating to race, royalty, religion, defamation, impersonation,…