Haha not quite as common as back bacon I would say, more just a funny name a few folks swing around if they are lucky enough to have heard it before. Plenty of Canadians that have never heard that one before I would bet
We definitely have some slang differences like the British folks do though. I wouldn't call an apartment a flat or say pick me up a bag of crisps. But we do call a can of soda, a can of pop. Stupid little differences like that. I think it's the best way to sum up Canadian culture, its a heavy mixture of British and American influences.
I went decades before I realized the rest of the planet didn't know what the hell a toque was. I respectfully decline to ever call it a beanie or a knitted cap. They can have singlet or tank top while they are at it too. Wife beater is much more satisfying to say, well since it's 2020 we can update it an call it partner beater if that makes anyone feel better.
Gotta say it kind of loses it's ring though