We have the same problem. I noticed that this happens when the grid contains a lot of elements.
Can I have another question in the topic? Can you make it possible to set the parameters of the section plane manually (as in postprocess)? Because it is very difficult to achieve an exact cross section in the area of interest by using only sliders and this is annoying a bit especially considering that each time you have to wait until the cross section is drawn.
Yes the mesh clip dosen’t really work for meshes with alot of cells. But if you have paraview you can check the mesh offline really quickly. Just download the mesh, insert a empty text file. Rename the extension of that text file to .foam then open ParaView and select that .foam file to see the mesh.
ParaView is heavily dependent on the CPU and RAM. No worries though, 16GB is enough but you may have to wait quite a bit for meshes that contain more than 5 mil cells. RAM is relatively cheap now so maybe consider adding another 16GB set.