The two singers checked out M83's headlining show at the indie music festival and posed for pictures.
RELATED: Katy Perry says 'fame is disgusting'
And one fan says the romance isn't over, telling blogger Perez Hilton Perry and Mayer were all over each other.
Perry was reportedly left heartbroken after Mayer ended their short-lived romance last month. Neither Mayer nor Perry have addressed the romance or the break-up reports.
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