first of all: thank you very much for making Mattermost available! It is a really valuable tool during Corona crisis home office period.
My suggestion: It would be great, if the users could specify the syntax which they use in chat to format their messages.
For people like me, who were socialized in Usenet and who use
_underlined_ since multiple decades for formatting their messages, the Markdown syntax is really counter-intuitive and contra-productive. Since the days of Netscape Mail, the Usenet style text formatting has been the default in Mozilla Thunderbird (including the latest version) and is probably also implemented in other email clients (and of course in Emacs org-mode).
I’m aware that especially younger people (who do not know the Usenet) like the newer Markdown syntax. As it seems to be a matter of taste, habit, and probably also of age, it would be great, if the user could configure which syntax he/she wants to use for formatting his/her text input.
Dr. Christian Borss