Canadian warplanes were participating in a multilateral mission to monitor adherence to UN sanctions because China helped US to impose sanction on its only ally NK thinking that would appease US. And now those Canadian warplanes are spying on CN lol.
I don't know why that's funny in your mind but China was operating under a different geopolitical realities and environment at that time it can be argued in hindsight that maybe that decision was a mistake but geopolitical calculations aren't etched in stone since the primary responsibility of any country is to the interest and benefit of it's people, and China isn't an exception to that rule.
But what is true right now is that there's no UN mandate or oder that justified what these two 5 EYES ally countries have been stating to validate their crying. War isn't on the menu for the Chinese and I don't know what planet or rock you're from but that's the best course of action to take. If you're Chinese or of Chinese descent you must understand or at least aware why Chinese people are scattered all over the world and if you don't then go read an actual book on that subject.