There is this long-standing bug on mobile versions of slack where large swaths of messages just disappear. The only way to get them back is to sign out and sign back in. This is supposed to replace business email?
The UX around GitHub must be incredible for non-developers, because I am watching project managers with zero engineering/coding background learn markdown syntax almost accidentally. In all of our time using GH issues as a collaboration tool, I have heard exactly ZERO complaints regarding anything being broken or unfriendly to use.
We now look back on Teams/Slack/Skype/Email usage as dark days. "How the hell did we ever get anything done?" is the usual take when one of us talks about it.
git grep finds them.
Github could have put all the issues into the same repository, and built on top of that for the sake of managers, but that would make projects too portable. Having important project metadata in their domain aids lock-in.