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            <b><a class="bz_bug_link 
          bz_status_NEEDINFO "
   title="NEEDINFO - 3-fingers touch occasionally fails to get detected"
   href="https://bugs.freedesktop.org/show_bug.cgi?id=105043#c10">Comment # 10</a>
              on <a class="bz_bug_link 
          bz_status_NEEDINFO "
   title="NEEDINFO - 3-fingers touch occasionally fails to get detected"
   href="https://bugs.freedesktop.org/show_bug.cgi?id=105043">bug 105043</a>
              from <span class="vcard"><a class="email" href="mailto:Hi-Angel@yandex.ru" title="Hi-Angel <Hi-Angel@yandex.ru>"> <span class="fn">Hi-Angel</span></a>
</span></b>
        <pre>(In reply to Peter Hutterer from <a href="show_bug.cgi?id=105043#c9">comment #9</a>)
<span class="quote">> run libinput debug-events --verbose at the same time, that give you more
> debugging output and you can tell what tap state a touch is in and what palm
> state it is in. if a finger is detected as palm it'll be reflected as such,
> and if there's too much movement to cancel the tap, it'll show up as well.</span >

Thanks, I managed to get it, though don't really know what to make of that
info:

Sample from evemu-record | grep BTN_TOOL:


        E: 29.585448 0001 0145 0001     # EV_KEY / BTN_TOOL_FINGER      1
        E: 29.625140 0001 0145 0000     # EV_KEY / BTN_TOOL_FINGER      0
        E: 29.625140 0001 014d 0001     # EV_KEY / BTN_TOOL_DOUBLETAP   1
        E: 29.769373 0001 014d 0000     # EV_KEY / BTN_TOOL_DOUBLETAP   0

Acc. output from libinput debug-events --verbose:


        event10 - palm: keyboard timeout
        event10 - pressure: begin touch
        event10 - button state: from BUTTON_STATE_NONE, event
BUTTON_EVENT_IN_AREA to BUTTON_STATE_AREA
        event10 - button state: from BUTTON_STATE_NONE, event
BUTTON_EVENT_IN_AREA to BUTTON_STATE_AREA
        event10 - gesture state: GESTURE_STATE_NONE → GESTURE_STATE_SCROLL
        event10 - gesture state: GESTURE_STATE_SCROLL → GESTURE_STATE_SCROLL
        event10 - gesture state: GESTURE_STATE_SCROLL → GESTURE_STATE_SCROLL
        event10 - gesture state: GESTURE_STATE_SCROLL → GESTURE_STATE_SCROLL
        -event10  POINTER_AXIS     +33.50s      vert 2.73* horiz 0.00 (finger)
        event10 - gesture state: GESTURE_STATE_SCROLL → GESTURE_STATE_SCROLL
         event10  POINTER_AXIS     +33.52s      vert 1.46* horiz 0.00 (finger)
        event10 - pressure: end touch
        event10 - button state: from BUTTON_STATE_AREA, event BUTTON_EVENT_UP
to BUTTON_STATE_NONE
        event10 - button state: from BUTTON_STATE_AREA, event BUTTON_EVENT_UP
to BUTTON_STATE_NONE
         event10  POINTER_AXIS     +33.57s      vert 0.00* horiz 0.00* (finger)</pre>
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