Kubuntu 21.04 webcam support

Hello,
I have been using Zoom on Kubuntu 20.10 successfully for quite a while. I also installed the “cutting edge” Kubuntu 21.04 (with KDE Plasma 5.21) a couple of days ago. While my webcams work o.k. on Kubuntu 20.10, they don’t work on the upcoming 21.04. By the way: the webcams work under K 21.04 with Skype. Is anybody looking at that?
My webcams are:
Ricoh Co., Ltd Visual Communication Camera VGP-VCC9 [R5U870] and
Generalplus Technology Inc. HD 1080P WebCam (which I prefer!)
Thanks for any comment
Regards from Austria
H. Stoellinger