Which @angular/* package(s) are the source of the bug?

core

Is this a regression?

No

Description

When using multi-slot content projection these selectors are not working:

• :first-child
• :last-child
• :nth-child(x)

Please provide a link to a minimal reproduction of the bug

https://stackblitz.com/edit/angular-wmr4jp?file=src%2Fmain.ts

Please provide the exception or error you saw

No response

Please provide the environment you discovered this bug in (run ng version)

No response

Anything else?

No response