Message Archive Mgmt, server-stored chat history (this + carbons gives you chat sync on par with skype).
> history search
Client app matters. I don't see this function in Conversations (Android), but it is in Gajim and Mcabber, to mention few.
> editable messages
Sure, XEP-0308. E.g. Gajim enables you to do that. Ctrl+UpArrow and you are editing it, then your conversation/groupchat peers see it edited.
> embeddable rich content
Images and markup? Sure. Don't know about GIFs, well, maybe that's why Slack took off - better support for GIFs.
> reliable interop
I think this is not quite fair complaint towards software ecosystem which is currently mostly not supported financially.
Indeed, this is quite the problem keeping XMPP and mere mortals apart, but XMPP is closer to reliable interop than yet-another-new-slack-killer-company or NIH-driven-community-project. Keep in mind huge variety of existing software and amount of problems resolved. Let's stand on shoulders of giants, not on the mere ground.
> my mental model of how a message I create will appear to my viewers doesn't need me to understand 100 different clients and their quirks
Not an XMPP problem. In open world, you are safe to assume variety, not sameness.
I love my scriptable terminal-based chat client, are you going to deny me in having one?
I want a text-to-speech generator to read your messages to me, and free protocol enables me to do that, is your mental model of your message disrupted?
I want to have your message translated by some engine and presented in different language, is your mental model of your message disrupted?
Or, I am blind and I use Braille terminals, are you going to deny me in using it?
Don't see what to reply here
> push notifications
Solved https://github.com/siacs/Conversations#how-do-xep-0357-push-...
> "message was only sent to my other client and I didn't see it"
Message Carbons XEP-0280, implemented mostly everywhere (except Pidgin)
> scrollback
Message Archive Mgmt, server-stored chat history (this + carbons gives you chat sync on par with skype).
> history search
Client app matters. I don't see this function in Conversations (Android), but it is in Gajim and Mcabber, to mention few.
> editable messages
Sure, XEP-0308. E.g. Gajim enables you to do that. Ctrl+UpArrow and you are editing it, then your conversation/groupchat peers see it edited.
> embeddable rich content
Images and markup? Sure. Don't know about GIFs, well, maybe that's why Slack took off - better support for GIFs.
> reliable interop
I think this is not quite fair complaint towards software ecosystem which is currently mostly not supported financially. Indeed, this is quite the problem keeping XMPP and mere mortals apart, but XMPP is closer to reliable interop than yet-another-new-slack-killer-company or NIH-driven-community-project. Keep in mind huge variety of existing software and amount of problems resolved. Let's stand on shoulders of giants, not on the mere ground.
> my mental model of how a message I create will appear to my viewers doesn't need me to understand 100 different clients and their quirks
Not an XMPP problem. In open world, you are safe to assume variety, not sameness. I love my scriptable terminal-based chat client, are you going to deny me in having one? I want a text-to-speech generator to read your messages to me, and free protocol enables me to do that, is your mental model of your message disrupted? I want to have your message translated by some engine and presented in different language, is your mental model of your message disrupted? Or, I am blind and I use Braille terminals, are you going to deny me in using it?