Search results that don't allow you to go to the specific part of long conversations. Wiki that doesn't even qualify as wiki. Integrated calendar that automatically tries to make you join meetings you have not yet responded to (with no way to configure not to happen). Inconsistent ability to quote reply to peoples messages. Hap-hazard method of starting meeting recordings (anyone can do it and with the latest update they become the owner instead of the meeting organiser). External guests can't access meeting recordings. Inserts non visible spaces into code you paste in and does not strip it properly when copying and pasting out. Emoji selection popup fails to load if you join a meeting with busy chat as loading new messages takes priority. Inconsistent loading of tabs when you join a meeting, so some people cant do Q/A or look at files (but can be loaded in a separate window even whilst the meeting is running. Bigger issues like high CPU usage (massively compared to Zoom) with lots of attendees and far more limited visible attendee screens (compared to Zoom).
At the moment obvious defects seem to be added faster than they are removed.