FME Desktop 2020.0.0.0: What is the best practice to fix issues identified by “geometry validator” tool?

There is no hard and fast solution for geometry issues, it is all dependant on exaclty what the issue is. If you open the Feautre Information window

You'll then see a list of issues, some issues are subsets of others and may appear multiple times.

That one feature fails both OGC Simple and OGC Compliance because of a self intersection, and it also fails the seperate Self Intersects in 2D Testthe other output ports are detailed here: http://docs.safe.com/fme/html/FME_Desktop_Documentation/FME_Transformers/Transformers/geometryvalidator.htm

Hi @jamal​, you can either hold the ctrl key and select multiple green magnifying glasses to view the errors in the entire drawing. You can also just click on the top of the transformer itself, with nothing else selected in the workspace, and this should open all output ports in the visual preview window.