Product group behaviour

Hi,
I made 8 groups and created about 200 products distributed in those groups.
When I create an invoice I can click “Add product”. I then get a list of all products in all groups. I can scroll down to select some products and add those to the invoice.
However, when I select a group, I can’t scroll down to select some product that’s not on the screen. The scrollbar is there, but does not work. Scroll wheel does not work also.
When I select a product that is on the screen, I can’t add it to the invoice because the “add” button is not accessible.
InvoicePlane 1.5.3 is running on a linux-machine. Browser is Firefox 52.1.1 on linux (Opensuse Leap 42.1). Same problem with Chromium 58.0.

Is this a known bug ?
This is a new setup, to test and learn.

TIA

Will test this and repot back later

Any progress ?
If you like, I can send you my database.