Mattermost vs. Signal?

Hey all, I’m new to digital security. I’m currently working with a team on Signal. The issue is that since we’ve grown, it’s become pretty frustrating and disorganized to communicate with 30 people in a single chat. I would like us to move to a platform like Discord - however I have concerns with that platform’s security, so now I’m thinking about moving us to Mattermost. I’m wondering how tight the security is on Signal vs. Mattermost? Any information is …

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