unity - system freeze after login in 18.04 gnome

I recently upgraded my system to Ubuntu 18.04.
After I login in Ubuntu or Ubuntu on Wayland mode the system freeze. I can move my mouse. I can switch to tty3 with Ctrl+Alt+F3. But I could not actually click on any icon or button. Neither can I open the terminal with Ctrl+Alt+T.

However, If I log in with Unity shell, everything seems fine.
I have tried the solutions in following posts but did not work.

My laptop is Dell XPS 15.
Linux XPS 4.15.0-22-generic #24-Ubuntu SMP Wed May 16 12:15:17 UTC 2018 x86_64 x86_64 x86_64 GNU/Linux

Please let me know if there are any ways to solve this issue.

I was finally able to use gnome-shell. After I removed all the gnome extensions, the freeze issue was solved.
You can try to remove all the gnome extensions from ~/.local/share/gnome-shell/extensions and reboot.