it's working as I can see the CPU temp, but there is no auto refresh of the number. Also Sys temp (Mainboard) is missing, but I assume that's an issue with the underlying lm_sensors app. A resize of the window is required, otherwise there is only a black square window with nothing in it. The website seems to be dead. I prefer Sensors Monitor over this one.
When I open it, I get a microscopic window, I think the size is 10 x 10 pixels. I have to expand it. It does not refresh the window properly. Parts of the window is whatever the background is. The temperature that it shows is 0 C for CPU and 0 C for System. It does not appear in the start menu. I have Linux Mint 19.3.