Is Muslim Marseilles safe for a single white gay male?

I work for a French multinational and next September will have to go their Marseilles offices for a couple of weeks. I don't usually worry about this kind of thing because I have been lucky to live in big gay-friendly cities like Barcelona, where I grew up, London and Paris. Marseilles makes me worry though, because of its violent fame. I am especially worried at the homophobic reputation of its Muslim population. Is a single gay male safe in that city? I am quite flamboyant and not especially sturdy so I fear being targeted. What should I do?