Here the same problem with the same version. I’ve waited during 2 hours, my PC is veeery bad, but it can runs perfectly UE4 version 1.12.5, but I don’t want to use this old version because there aren’t the features what I need.
When I open UE4 1.18.3, the loading screen freezes and the ‘Initializing…’ points are freeze. I can’t go to my projects panel and the create projects panel, this happens when I open the editor.
And I have only 2 projects: 1 of the simple third person and another for mobile with only 3 super-low-poly models and 2 textures. Help 
(I known, Im not the OP)