Hello.

Just to confirm that now, after several tries, the freeze starts 2 seconds after
the double clic, and lasts for 18 seconds afterwards (first after boot, as usual,even if it is one hour later).

Is it because of the 'updates cleaning' ? I don't know

Also, someone said thet 'bonjour' was related to 'calibre companion'. I never installed this, and I don't have any android device.