Exporting unity project doesnt work at all

I have kinda of a big game, big enough to not be able to use collaborate. I have set up git for my project however, the first transfer to my other computer i would like to have the complete project there. When i click Assets>Export Package the dialog box that appears just thinks, until it stops and no files are shown at all. just a blank window where i should be able to select what I want to export

anyone that has experienced this before?

on Unity 2019.2.17f1