Just an idea, are any/all of you running multiple screens? I am. One is on an NVIDIA GTX 1080 and the other on Integrated Intel HD Graphics.
did you also restart termius?
It doesn't seem to happen if you turn of the "Use new terminal rendering engine", but then there are the text select issues and sometimes some artifacts.
Same here, gradual ram creep and frequent periods when it become unresponsive and uses 100% cpu on a core.