I've used Cura 3.0 through 3.3 reliably with Octoprint, but since moving to 3.4 and 3.4.1, it has worked less well. The most common problem I see is that after the first job I have sent to the printer the next one will not starts. Either the Print With Octoprint button does nothing, or it tells me there is a job in progress and offers to queue the next one. The last time this happened, I noticed that on the Monitor tab in Cura, the job was shown as only 34% complete when it was fully done. So I wonder if there is a problem in Cura querying state from Octoprint. Clicking Abort Print did not fix this, but clicking Pause then Resume set the state to complete.
I don't know if there is an existing bug for this, or how I should report it. I'm happy to look for logs etc if it helps.
My set up is Cura 3.4/3.4.1 on Windows 10, talking to Octoprint 1.3.8 on a Raspberry Pi over a local network, and the Pi then communicates over USB to an Azteeg Smoothieboard clone.