Boygenius' Julien Baker and Lucy Dacus also feature along with Jack Antonoff and Christian Lee Hutson
It marks her first new music of 2026
The evening also saw performances from Clairo, Geese, Pedro Pascal and more
Boygenius had previously worked the song - associated with the women's suffrage and labour movements - into their own song 'Stay Down'
It will also be hosted by Pedro Pascal with additional performances from Daniel Caesar, Shawn Mendes, Faye Webster and more
"I was backstage and I was like, this is what I want to do"
Earlier this year, Clairo was praised by Bernie Sanders for her ardent support of Gaza, and now joins the likes of Lorde and Hayley Williams in adding her name to the cause
She was also joined on stage by Zohran Mamdani, Democratic nominee for New York mayor
She has also updated the official artwork for her recent album 'Forever Is A Feeling'
Dacus asked fans who attended the Montréal festival to share footage of the moment with her after the show
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