Thanks Antonio - I'll take a look.
many thanks again for bringing this issue to my attention.
I have fixed this issue in the latest release of the HotPot module.
Please arrange for the HotPot module on your Moodle site to be updated at the next convenient opportunity.
For people using TaskChain, I have also fixed the "Select All/None" functionality on TaskChain for Moodle >= 3.3.
The latest version of TaskChain, release 2017-10-04 (52), also fixes an issue that appeared in release 2017-08-29 (50), whereby it was not possible to edit TaskChain settings or create a new TaskChain, My apologies to anyone affected by that bug, and my thanks to user "UVa Uva" for bringing it to my attention.