Datefield does not validate (NL locale)

[micschk]

When a userform in NL locale includes a date field, it cannot be submitted because the date is considered invalid.
I've found some comparable resolved/closed issues but this is happening on a site which is on userforms 5.9.2:

[micschk]

Upon investigating this further, seems to be an issue with jQuery validate.
See: jquery-validation/jquery-validation#2359
And: jquery-validation/jquery-validation#2360

Quick fix seems to temporarily block the localization altogether:

// Temporarily block jQuery validation localization because that breaks date inputs:
Requirements::block("silverstripe/userforms:client/dist/js/jquery-validation/localization/methods_nl.min.js");

[ovogel-wigital]

Had the some problem with locale de. Blocking localization helped but seems like a dirty hack. Issue should be reopened and investigated further.