function processChatMentions(mentions) {
	if (!mentions) {
		return mentions;
	}

	if (mentions.mention_accountids) {
		mentions.mention_steamids = mentions.mention_accountids.map(acctid => SteamID.fromIndividualAccountID(acctid));
		delete mentions.mention_accountids;
	}

	return mentions;
}
@param {object} mentions
@returns {{mention_all: boolean, mention_here: boolean, mention_steamids: SteamID[]}}