I also was pissed when the new update came out. If you miss the notifications, your fucked. Can't find them to click on and get taken to the conversation in the app, and the chat button next to the take a snap button is now gone. Thankfully, theres another way. If you turn off voiceover from the main screen when you first open the app, swipe right, then turn it on again and you should be at the chat screen. Maybe I'm the only one here who uses it, but I thought I'd post this in case someone out there is as confused as I was. Maybe I'll help someone, or maybe not lol just putting it out there if anyone needs it.
As far as playing audio messages within text conversations... I don't think theres a way to do that? Any tips anyone? I'm not on ios 14 so maybe the new recognition stuff helps with that? Or maybe were still screwed in that regard.