We only handle fake touches for devices without ABS_MT_SLOT. For those with real MT support, we merely ignore BTN_TOOL_DOUBLETAP and above. As a result, three-finger tapping is not available on those devices, or simply buggy (see bug 76760#c15). Solution: handle BTN_TOOL_<n>TAP for any n greater than the number of slots.
This is fixed by this commit: http://cgit.freedesktop.org/wayland/libinput/commit/?id=64f431c303fab787eaf8a7cb14752d908b3da8b2 Closing.
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