Reading a session variable in CI3 that was set by CI4

CI3 Session class cannot read CI4's Session data because the definitions of the session table are different.
Therefore, CI3 Session must be modified to be able to read CI4 Session data.

Can you clarify this?  Are you saying that if CI3 is setup to read and write to the CI4 session table by using the same $cookieName and the same $savePath, then CI3 can read session info written by CI4?  Or, are you saying that the actual code for sessions in CI3 must be modified in order to read CI4 session data?

The comments in  CI4 app/Config/Encryption.php seem to imply that there are settings that will make it possible to read and write sessions that are compatible with CI3. For example: 

Code:

   
    /**
    * Whether the cipher-text should be raw. If set to false, then it will be base64 encoded.
    * This setting is only used by OpenSSLHandler.
    *
    * Set to false for CI3 Encryption compatibility.
    */
    public bool $rawData = true;
    ...

So, are there settings that can be used that will allow CI4 to read a session written by CI3 or write a session that CI3 can read?   That is what I am looking to do.  

BTW, the below did not work.