Catallina installer

[bill99]

Hello forum

Need to "downgrade" a iMac from Big Sur to Catalina and I heard this can be done using a custom made installer
(because my main-app does not yet fully support BigSur and others)

Question:
1.
Does such an installer contain the whole macOS or does it "only" download and install Catalina?

2.
Should this procedure work without AppleID?


Thank's a lot for any feedback!

Bill

 

[tommiy]

Look on Apple Support here. Its the entire OS and you do not need an apple id to run it.