mtranchina

YES! Would love to have open-source alternatives available... Mattermost is very similar to Slack and is an ideal and needed integration since Slack seems to be such an integral tool...

Same... 

Checking...

Yup...That was the problem...When accessing from outside my network using DDNS and HTTPS it works fine...Using my internal IP HTTP gives me that error... Thanks!

Now I just need to replace Slack with Mattermost! ;-)