There seems to be a regression on graph visualization (since the adaptation to sigmaJS updates ? @karenkonou )

Links are very thin and some even seem to be at width=0 (see for example https://dev.sub.gargantext.org/#/share/NodeGraph/189445 )

Or maybe it's because of the addition of an alpha value. But even in this case, the witdh of the edges should be positive.

For most proximity measures, edges values are between 0 and 1, so width should be set to something like (a + b* edge_value) so that we can distinguish strong links from weak links.

Start testing with a=2 and b=5 and adjust according to the rendering. With an alpha on links of about 60% this should provide a good rendering.