I'm Australian and flying this afternoon from China to Mexico with a long layover in Vancouver.
I kind of knew Canada had this
eTA thing but assumed I wouldn't need such a thing as an Australian who's been to Canada several times in the past and doesn't intend to leave the airport this time.
But as I was getting stuff ready last night I found a couple of websites warning me that even as an Australian and even not intending to actually enter Canada I might still need an eTA!
Other sources I can find vary about 50/50. I think I don't need one but it would be bad if it turns out I do.
(By a stroke of luck the StackExchange CDN is in my laptop cache due to VPN working briefly at one point. It's not working again now...)
So do I need an