I have tried to do a grid volume run with the Saga grid calculus - grid volume function. After the run the window closes and nothing seems to happen, no message, no new layer or information appear. I use a raster .tif as input.
After a run, where does the output normally appear?
This issue was also reported here a while ago.
The numerical result is printed in the Log Messages Panel which you can access by right-clicking the toolbar until you see a list of options and enabling the said panel.
I did a test run and if you scroll down the Processing tab, you will see an output that's saved in a Temp folder (although I can't say if it has been modified or if it's the same as the input). But further down you will also see the result which contains the Grid Volume:
