Editor freezing when I drag and drop prefab into the scene

Hi Guys
Editor freezing when I drag and drop prefab into the scene. Even if I use a prefab in the scene game takes around 1.5 minutes to play.
unity version: 2019.4.0f1(this issue was also happening with 2019.3.13f1).

Please help me fix this issue, my project is completely stuck right now. Thanks.

Ok. How big is your prefab and your levels? And also maybe, maybe Its cuz you have a bad pc (like me).
And is this haapening in other unity versions like 2018, 2020, 2019.2f etc.

I have got freezing problem before, and I solved it be turning on the metal editor, but I have got a Mac. Changing layout may also help.