Filipino Citizens – Traveling through Canada with China Southern, required in transit visa while quarantined in the "sterile transit area"?

I am a Filipino passport holder. No US visa, no Canadian visa. I am flying from Costa Rica to Mexico City. Then Mexico City to Vancouver, China, then the Philippines. I get to China City on flight number 378 and land at Vancouver Terminal M. The same flight number on the China Southern 378 and the Terminal M and even the same place goes all the way from Vancouver to Guangzhou. The stop in Vancouver is 1 hour 50 minutes. We have to get off the plane. The Canadian website on transit immigration is very unclear. If you stop off on an international flight, you remain "in the sterile transit area" while you are transferring to the same flight as me. I mean, we get off the plane, stand no longer than 1 hour and 50 minutes in the "sterile transit area" and then get back on the plane. If no special visa is required, is that correct? Has anyone done that?