I am trying to use union processing on a number of overlapping polygons (approx 50-100) in the same layer. This raises the error "GEOS geoprocessing error: intersection failed", without any further details.
I have tried "check validity", "fix geometries", "check geometries" and "topology checker" on my data, and none of them show me any errors. I have tried this both in 3.22.3 and 3.16.16 (LTR).
I think this thread talks about the same problem (albeit without providing any helpful solution): https://github.com/qgis/QGIS/issues/37032
Is QGIS just not able to handle Union-processing of this magnitude, or is there anything I can do?