For libinput properties of xinput, whats the difference between those with default in their names and those without?

Question

For xinput list-props "ETPS/2 Elantech Touchpad" my output is

Device 'ETPS/2 Elantech Touchpad':
    Device Enabled (139):   1
    Coordinate Transformation Matrix (141): 1.000000, 0.000000, 0.000000, 0.000000, 1.000000, 0.000000, 0.000000, 0.000000, 1.000000
    libinput Tapping Enabled (276): 0
    libinput Tapping Enabled Default (277): 0
    libinput Tapping Drag Enabled (278):    1
    libinput Tapping Drag Enabled Default (279):    1
    libinput Tapping Drag Lock Enabled (280):   0
    libinput Tapping Drag Lock Enabled Default (281):   0
    libinput Tapping Button Mapping Enabled (282):  1, 0
    libinput Tapping Button Mapping Default (283):  1, 0
    libinput Accel Speed (284): 0.000000
    libinput Accel Speed Default (285): 0.000000
    libinput Natural Scrolling Enabled (286):   0
    libinput Natural Scrolling Enabled Default (287):   0
    libinput Send Events Modes Available (261): 1, 1
    libinput Send Events Mode Enabled (262):    0, 0
    libinput Send Events Mode Enabled Default (263):    0, 0
    libinput Left Handed Enabled (288): 0
    libinput Left Handed Enabled Default (289): 0
    libinput Scroll Methods Available (290):    1, 1, 0
    libinput Scroll Method Enabled (291):   1, 0, 0
    libinput Scroll Method Enabled Default (292):   1, 0, 0
    libinput Disable While Typing Enabled (293):    1
    libinput Disable While Typing Enabled Default (294):    1
    Device Node (264):  "/dev/input/event5"
    Device Product ID (265):    2, 14
    libinput Drag Lock Buttons (295):   <no items>
    libinput Horizontal Scroll Enabled (296):   1

So what's the difference between something like libinput Tapping Enabled and libinput Tapping Enabled Default? What does default mean in this context? I am using it to set up my touchpad for i3.

Answer 1

xf86-input-libinput uses these read-only properties to report default values that libinput would have used for this particular device, and therefore allow UIs & control panels to correctly reset the parameters, instead of them having to assume a single default on all systems and devices (or duplicate libinput's logic).