If using the 'Disable long inserters' option in the mod settings, i've noticed a couple of small QoL bugs:

• the default upgrade planner will downgrade a regular inserter to a long inserter. it also shows up in the upgrade planner as a selectable entity if manually creating an upgrade/downgrade blueprint

• the item is still shown in factoriopedia.

if i had to guess, the entity still exists because you don't want to remove it from a save game if someone changes the mod settings. but the downgrade path should be fixable?

OK so I checked and Factorio added a bunch of new flags for the Factoriopedia, I'll experiment a bit with the downgrade and for the next release should be fixed, Ill notify here if something is problematic to fix.

So factoriopedia should be fixed
Long inserter should not appear inside the upgrade planner

But I could not figure out what you mean by downgrade, factorio supports only next_upgrade

P.S. I'm considering adding them back in the upgrade planer to allow a quick swap between long and normal inserter, for now they will disappear

downgrade being the right-click drag on the upgrade planner, which will mark entities to be swapped with earlier versions

changing it would depend on whether you can specify only the direction, if internally that make it show for both directions then it's unlikely it'll be able to be changed

In the way it works right now long inserter should be completely ignored in the upgrade planner so should work just fine, ill keep this thing in mind if a better solution comes up.