Bug: Timepicker not working when run via ng serve with other locale

It seems that timepicker has a bug, that prevents it from working when the angular SPA is run via ng serve with a non-default locale.

I am working on an angular SPA that is developed with English as its default locale. It has also support for German via angular i18n. For testing, I have two different run configurations to start my SPA either with the English or German locale. I have recently noticed that my angular components crash (page stays blank) in the German version, after I've added a timepicker. In the browser's console the timepicker prints the ERROR TypeError: $localize is not a function.

Luckily this error only occurs when using ng serve. The version compiled with ng build (which includes both locales) is not affected by this bug.

I made a small example project, that highlights this bug: https://github.com/LUC4R4T0R/ng-bootstrap-timepicker-localize-error .