Any good suggestions for a self-hosted free team chat service (Slack alternative) that fulfils these requirements?
Although both Slack and Microsoft Teams fulfil the needs they are costly to use and for example, Slack cannot be self-hosted.
We're looking for this type of basic functionality so please check before suggestion a product whether it actually will allow these functions:
1. On-premise hosting (self-hosted)
2. Preferably open source software and must be free to use.
3. Built-in or integrated video/audio conferencing for multiple people with screen sharing eg. like Jitsi (Essential)
4. Real-time collaborative document editing like Etherpad (this is not essential) as we could host Etherpad on the same server)
5. A hosting instance should allow for private/public channels which can be subscribed/unsubscribed by users
6. Threaded discussion topics in each channel so that replies are grouped together.
7. Polls/Surveys to test opinions or to vote on something
So after looking at Riot, Zulip, Mattermost, HipChat, Rocket.chat, etc the closest I have found is Riot (https://riot.im) which has Jitsi video conferencing and Etherpad document collaboration neatly built in, but they have not yet released threading for their channels, nor do they have any polls/survey integration that I can see.
Yes I realise G+ may well do a lot of this but we can't host it on our premises. But any good suggestions will be most appreciated and maybe others will learn something from it too.