If i google “deserializer.cc” i get a link to the git of chromium.
so maybe your chromium installation is broken.
Did u use the automatic installer or not?
Maybe you should delete the MagicMirror folder in your home dictionary and try this if u use a raspberry pi:
bash -c "$(curl -sL https://raw.githubusercontent.com/MichMich/MagicMirror/master/installers/raspberry.sh)"
And u should read this carefully:
https://github.com/MichMich/MagicMirror
Aaaaaand u should edit your post as MadScientist said ;)