Thanks. I rolled back by changes and described the config below $HOME in my internal readme as:
The vibration can be switched off by modifying the file a local
copy of the defaul.json file:
mkdir -p ~/.config/feedbackd/themes
cp -p /usr/share/feedbackd/themes/default.json ~/.config/feedbackd/themes
modify in the local default.json file the 10000 to 0
in this section (line 134):
{
"event-name" : "phone-incoming-call",
"type" : "VibraPeriodic",
"duration" : 10000
},
SIGHUP the feedbackd:
ps ax | grep feed
1458 ? Sl 0:48 /usr/libexec/feedbackd
sudo kill -HUP 1458
Works fine!