I have been trying to plot my variables over time. To do this I have selected the cell(s) in question and then click “plot over time”. This seems simple enough.
Unfortunately when looking at a 3D shape of my results and change the time step, the selected cell moves. I am using version 5.8.0. Has anyone else seen this problem before or knows how to fix it?
The answer probably depends on how you selected the cell and the nature of your data. I’m going to assume that you selected the cell by clicking on the Select Cells On button 
and clicking on the cell.
Most likely what is happening is the topology of your mesh is changing from one timestep to another. When you do a selection like this, ParaView records the id of the cell you selected (cells are ordered from 0-N). If you load a mesh for a new timestep and the mesh for the next timestep has the cells in a different order, then the selection is going to move.
If you want data to be at a consistent location over time, you might try the Probe filter instead.
I met the same problem here. My data is 3D so a volumetric mesh but I want to analyze the surface values so I applied ExtractSurface. The selected cells on the 3D mesh didn’t change with time steps but the selected cells on the surface did. I tried Generate Ids and Generate Global Ids but neither works. Perhaps is the ExtractSurface filter change the cell order for every time step? Is there a way to avoid this? Thanks in advance!
