Around here (Brazil), during manifestations, the police will search every bag they can see. While the clothes alone are obviously “nothing”, I wouldn’t be surprised if they came up with bullshit reasons to take you away or keep a very close eye on you, or if some damning evidence “magically” appeared.
If you’re that paranoid, or there’s an actual crackdown happening, stash the backback and retrieve later.
Around here (Brazil), during manifestations, the police will search every bag they can see. While the clothes alone are obviously “nothing”, I wouldn’t be surprised if they came up with bullshit reasons to take you away or keep a very close eye on you, or if some damning evidence “magically” appeared.