Here's the link: https://www.thestar.com/news/gta/2021/05/20/toronto-police-remind-officers-to-stick-to-uniform-after-thin-blue-line-patches-spotted-at-homeless-clearance.html

Basically a few officers were seen wearing a thin blue line patch. These patches have a black and white Canadian flag with a blue line across the middle. I had never heard of this before today, but the article says that these patches are associated with the "blue lives matter" movement which is why they are controversial, however officers claim they represent fellow officers who have died while working as a police officer.