It happens that there is a bug/incompatibility between Qt libraries and Google Earth in a way that comma are interpreted as point and viceversa in locale environments where comma is used to separate decimals and point as a thousand separator.

Find the bash executable of GE : in my system /opt/google/earth/free/googleearth

Just before the last line
LD_LIBRARY_PATH=.:$LD_LIBRARY_PATH ./googleearth-bin "$@"

put

Re-execute GE and enjoy!

Thanks to pete.dawgg for this hint