I've found something interesting for settings via PrefPane
So, who has an empty prefPane when you installed a fresh copy of modern system 10.12+ and you want to make some settings in it. Like to enable Clicking.
By default PrefPane saves it's settings in plist file located at
~/Library/Preferences/com.apple.AppleMultitouchTrackpad.plist
and by default sometimes earlier you can enable Clicking via Terminal:
defaults write com.apple.AppleMultitouchTrackpad Clicking -bool true
but something went wrong (AAPL cheers) and a Key 'Clicking' has a wrong value format. It should be bool but has an integer. So we have to fix this issue
integer --> bool
Open this file with your editor.app (PlistEdit for ex) and fix this:
to this
and then reboot or reenter account.
Voila! Your prefPane will work properly.
EDIT: Also I tried to revert this value format to the wrong one (integer --> 0) and reentered acc. PrefPane worked after all. Setting 'Tap to click' was enabled but no clicking was physically. Then I tried two commands:
defaults write com.apple.AppleMultitouchTrackpad Clicking -integer 1
defaults write com.apple.AppleMultitouchTrackpad Clicking -int 1
without success. Then unchecked 'Tap to click' and prefPane automatically fixed in it's plist integer (0) --> bool (false). Checked it once more to enable Clicking and voila: plist file has bool (true) and everything is working fine.