Left-handed mouse: tap produces right click

First of all I’d like to say that documenting a bug doesn’t justify its existence.

The issue I am reporting is documented in `man synaptics`:

> If the device is switched to left-handed (an in-server mapping of physical buttons 1, 2, 3 to the logical buttons 3, 2, 1, respectively), both physical and TapButtons are affected. To counteract this, the TapButtons need to be set up in reverse order (TapButton1=3, TapButton2=1).

Steps to reproduce:

0) "Tap to click" is activated (by default), your computer has a touchpad
1) Switch mouse and touchpad to the left-handed mode through Settings > Mouse and Touchpad
2) Logout and login for the changes to take effect
3) Tap the touchpad

Expected result: a left click event is generated
Actual result: right click event is generated, context menu is shown

Steps to work around the problem (no sane person will consider this a real solution):
1) Find in `man synaptics` the lines quoted above
2) Find out the syntax of xinput to configure Tap Action (not in the `man xinput` since this particular case is not mentioned there, and not via xorg.conf which ceased to exist)
3) Run this command via an entry in .config/autostart (since putting it in .profile and .xinputrc doesn’t have any effect)

These configuration steps MUST NOT (RFC 2119) exist. Tapping the touchpad should continue to work normally even after switching the mouse to the left-handed mode.

For the next poor soul trying to figure out the command to run:
1) Run `xinput` and find your touchpad there, remember its ID
2) Run `xinput list-props <ID> | grep "Tap Action"`, remember property ID
3) Run `xinput set-prop --type=int --format=8 <ID> <PROP> 2 3 0 0 1 3 0` on login by adding it to "Startup applications"