steps to reproduce with the sample app:
go to http://localhost:4502/content/contextaware-config-sample/en/config.html
add new configuration "Sample Configuration 2"
enter a value "123,456" for "Double Param" (using "," as decimal separator, not ".")
expected: a decimal value with "," should not be accepted by the GUI validation, only with ".".
actual: "," is accepted by the GUI, but leads to an error in the backend when saving.
sidenode: tested on windows OS with german language.