Layer.visible property when using 'arcpy.mp.ConvertWebMapToArcGISProject'

Question

What determines whether an arcpy map layer that was created as part of a created created using ... result = arcpy.mp.ConvertWebMapToArcGISProject(WEB_MAP_AS_JSON)‍ can be turned off? I'm creating a map from the above... aprx = result.ArcGISProject mymap = aprx.listMaps()[0]‍‍ But when I try turn layers invisible, I get this for some: The attribute 'visible' is not supported on this instance of Layer.‍ The layers all derive from a Portal webmap so that they have... layer.isWebLayer = True‍ Most of my layers don't have that issue and wilingly switch to : layer.visible = False >> Success‍‍ Is this limitation based on a setting in the webmap or in the underlying map services (item) ? Thanks.

Arne_Gelfert · Answer

So I'm stumped on this one. I've gone ahead and republished my map service in question here, and now I'm seeing even weirder behavior. But since it doesn't merely relate to the 'visible' property, I'll start a new thread. Thanks for chiming in, Dan.

danretired · Answer

Arne Gelfert‌I don't know offhand since I am usually working with data I create myself... so everything is perfect of course 
.

If you get a list of layers that don't work, you may be able to determine some communalities between them... assuming that there isn't some random or obscure bug.

Arne_Gelfert · Answer

Sorry ,,, never a good idea to tweak things in transition from IDE to Geonet... I'm flipping the attribute to its Boolean opposite, so it should read: layer.visible = not layer.visible If it was visible to begin with, I want to hide it, and the other around. Any idea why this would fail for some layers? Thanks, Dan.