In PHP, the "Typed property must not be accessed before initialization" error is encountered when a property is defined with a type hint, but it is accessed before it has been explicitly assigned a value.
In PHP, using array and string offset access syntax with curly braces has been deprecated as of PHP 7.4.
This error message is indicating that you are trying to access an array offset (i.e., an element of an array) but the value being accessed is null.
To update PHP to version 7.4 on macOS Catalina using Homebrew, you can use the following steps: