Trouble with taking screenshots

[AL-Man64]

I'm using a hybrid of xfce4 with the qtile window manager, and whenever screenshoting with xfce's built-in tool, i get screenshots from a completely different screen/workspace or browser tab. I'm not sure if it's a bug worth reporting, but I am certain the problem is at least partly to do with picom, because when I kill it, the screenshoter works just as expected. Anybody has any idea what the problem is? Thank you in advance.