Wrong language used when selecting "system" language

Hi,

My system is set to U.S. English, yet when I select the “-- System --” option in the language settings tab, Seafile switches to Dutch, which is installed only as a secondary language pack (for spell checking purposes). Everything else on my system (Windows itself, other applications etc) are all in English, as expected.

It’s easy enough to manually select English for Seafile, of course, but I thought I’d report this as a bug anyway.