This question has been asked literally hundreds of times around the web with no real answer (other than to press Ctrl-U, which does not work). I just want to alter the default import obj preset (in my case I need Poly Groups checked by default) and the default export FBX one (needing no leaf bones).
I do NOT want to have to “choose” my own operator preset, even if I only have to do this once per session, because I invariably forget to do so and each and every time it’s a PITA. Plus – Blender allows infinite customization, and isn’t all the dialog boxes written in Python? Can’t somehow someone point me to where the import/export dialog boxes are written so I can alter them. I realize if I do then the NEXT release will overwrite this, but I can live with that.
I write this knowing I will get no good answers – as I said, everyone has asked and no one has given an answer – but I thought I’d give it one more college try. For over a decade folks have wanted this. Why can’t the Blender community make it happen?