Dear Firedrakers, Some queries: (a1) I have been updating one of the tutorials by adapting the python script of the BL-demo; how can I test its page, and where do I submit it as candidate update? (a2) In essence I updated the demo so that it has reduced output and reproduces the Figure 3 test of an associated publication, which figure I included as target for reproduction by any user, because then the user would know whether the outcome is right; also adding a small python script to visualise the energy (lower panel of Figure 3 attached). Since Figure 3a and 3b contain line plots at multiple times: rather than using an animation in Paraview: how can one with "Plot over line" keep multiple line plots at different time levels in one plot (since this would literally reproduce Figure 3a and 3b)? Also the old demo had some old expired links which I fixed. (b) Finally: with h_n0 = Function(V) on a 2D mesh, how can I find the maximum value on the mesh? This is in preparation for a potential flow test with a nonlinear, 8.4-fold amplification. I now use/added: ... from firedrake.petsc import PETS ... with h_n0.dat.vec_ro as hh: L_inf_err = hh.max()[1] ... but that seems a bit overkill? MPI next!?! Thank you and kind regards, Onno