No or can't find the desktop environment switcher

I just install Cutefish DE to try it with sudo pacman -S cutefish, when i reboot i can’t find where can i switch between Kde and Cutefish !!!
Should i ceate a new user for the new desktop environment ?

You should see a “Desktop environment Switcher” in bottom-left corner while logging-in. Choose “Cutefish Desktop” there.

No Desktop environment Switcher i try to change the login screen too !!!