I am trying to set up a QGIS project in Lizmap, but the problem is that I can't see polygons or lines vector layers.
They appear in the legend; I can zoom on them or use "select by location"; and I can edit them: I can change the attributes and even add new features. The features I add in Lizmap are correctly displayed if I open my layers in QGIS using WFS/WMS or PostGIS, and are saved in my attribute tables. But they are not visible in Lizmap (they "disappear" as soon as I finish drawing them in Lizmap).
The problem doesn't arise with "point" geometry: my points vector layers are correctly displayed in Lizmap, even if they have a complex symbology (heatmap). Raster layers (eg orthophotograph used as base layer) also display correctly. I did a few tests, and I have the same problem for shape layers used as base layers: they only show if their geometry type is "point".
I have no idea where the problem comes from.