I'm having this issue for the last 3 days that the internet doesn't work, even when connected with good signal strength. I get this question mark(?) inside the WiFi signal bar. WiFi works on Windows 10 and other devices so it's definitely an Ubuntu issue.
However, there's an anomaly. It works when it is just connected and stops working after a minute or two. Stops working when awake from a sleep. Starts working again when toggled on/off(not always, though). It also sometimes returns on its own for a short while and goes back to that question mark stage again. Very weird imho. I don't think it has anything to do with powersaving mode.
Any logs I could provide(and how)?