BeOS allowed widgets (I think was their term) whereby parts (or entire) of applications could be embedded in others - https://www.waltercedric.com/gadget/beos/

BeOS allowed widgets (I think was their term) whereby parts (or entire) of applications could be embedded in others - https://www.waltercedric.com/gadget/beos/ https://www.waltercedric.com/gadget/beos/ - https://www.howtogeek.com/696193/what-was-beos-and-why-did-people-love-it/ https://www.howtogeek.com/696193/what-was-beos-and-why-did-p... - https://en.wikipedia.org/wiki/BeOS https://en.wikipedia.org/wiki/BeOS