https://github.com/spantaleev/matrix-docker-ansible-deploy makes it easy to deploy.Not sure about the RAM limitation. If Synapse is too heavy, perhaps a different server (Dendrite?) will be light enough.
Matrix is in the process of being adopted as the MIMI standard by the IETF. At least it was one or two months ago.
There is also Element Call at call.element.io. I have not tried screen-sharing but it's worth a look.
qpdf is the best CLI tool that I have used to edit the structure of a PDF. I recommend it if you don't require a GUI, and do not need to edit the content.
https://github.com/spantaleev/matrix-docker-ansible-deploy makes it easy to deploy.
Not sure about the RAM limitation. If Synapse is too heavy, perhaps a different server (Dendrite?) will be light enough.