on #Linux (at least with xorg/cinnamon/fedora/whatever), SDL3 is picking up these phantom mouse up/down events that are mislabled as being from mouse 0, and this behavior differs from SDL3's mouse emulation (which I have off anyway).
something installed touchegg but I killed it with fire but that doesn't seem to have been the cause.
libinput by way of the debugging info provided by xinput seems to not be doing this, so that would leave xorg right? is there anything else I should check?