EDIT: no, all proprietary
"While no longer using an IRC backend, Slack offers many IRC-like features"...
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> i have a linode box that runs irssi in a tmux session 24/7 and that’s all it’s for.
Make of that what you will.
What I meant is use an open protocol to which simple applications (or whatever you prefer to use) can be plugged.
Because my company uses Slack I now have to use their stupid UI proprietary implementation.
I'm also annoyed that popular open source projects like Kubernetes moved to Slack because it's "discriminatory" to use IRC apparently.
> While we still use it heavily, IRC is an ongoing source of abuse and harassment for many of our colleagues
Have you tried wee-slack or similar?