What is the issue?
When using Google Chrome 92.0.xxx releases for AP Pro and regional setting set to nb-NO, the invoice doesn't display the correct format of the decimal separator and date format.
Chrome 92.0.4483 has a bug that removed localization support (date and number formatting) to several Norwegian dialects [details here]
Chrome fallbacks these dialects back to en-US which causes the incorrect formatting shown in AP Pro and many other modern web software relying on native browser APIs. This issue is known by the Chromium development team and is expected to be solved.
Until this issue is fully solved, we recommend to use as a browser like Firefox or Chromium Edge or change regional settings to fi-FI which produces the same formatting style as nb-NO i.e.
Numbers: 123 456 789, 12
And please remember that you can always enter the numbers without the thousand separators as well.
Latest updates on Aug 17th, 2021 by Chromium development team, the new released Chrome build 92.0.4515.159 has already the fix in place. So you may upgrade to that release for continue using nb-NO locale.