I've found a temporary solution for this bug, changing the LC_NUMERIC environment variable to "en_US.UTF-8".
sudo update-locale LC_NUMERIC=es_US.UTF-8
After that, the /etc/default/locale contains:
LANG="es_MX.UTF-8" LANGUAGE="es_MX:es" LC_NUMERIC=es_US.UTF-8
I suppose that the bug is related with the file /usr/share/i18n/locales/es-MX which contents the following lines:
LC_NUMERIC copy "es_ES" END LC_NUMERIC
However, try change this file and it had no effect with the decimal separator.
I've found a temporary solution for this bug, changing the LC_NUMERIC environment variable to "en_US.UTF-8".
sudo update-locale LC_NUMERIC= es_US.UTF- 8
After that, the /etc/default/locale contains:
LANG="es_MX.UTF-8" es_US.UTF- 8
LANGUAGE="es_MX:es"
LC_NUMERIC=
I suppose that the bug is related with the file /usr/share/ i18n/locales/ es-MX which contents the following lines:
LC_NUMERIC
copy "es_ES"
END LC_NUMERIC
However, try change this file and it had no effect with the decimal separator.