I noticed inconsistencies in the handling of the touchpad between different upgrades.
Following the last upgrade ot my system, the state of my touchpad tap can be summarized as follows:
I have to wait some seconds between successive tap before the new tap is recognized as a “left mouse button click” again.
So for instance If I open a new tab in the browser, I click on the “+” sign on my browser. By “click” I mean I press the touchpad.
Then I have to write a search term. I need to wait some seconds before I can “click” (press the touchpad with my finger) on the search bar. Otherwise nothing happens and the press is not recognized as a “left mouse button click”.
I hope I was able to expain it clearly 
It worked fine until the last upgrades…