mongoose.connection is undefined after 'connect' after library updates #13653

Prerequisites

Mongoose version

7.3.4

Node.js version

19.7.0

MongoDB server version

Atlas

Typescript version (if applicable)

5.1.6

Description

I did some experiments on a test branch that involved installing / upgrading several packages. None were related to mongoose, but I noticed that my app's initial connection attempt is failing with this error now:

TypeError:` Cannot read properties of undefined (reading 'on')

Which basically means that mongoose.connection is undefined even though I'm awaiting the connect method.

        await mongoose.connect(uri, options);
        // register event listener to track connection losses
        mongoose.connection.on("error", err => {
My connection routine has an automatic retry, and it fails reliably on the initial attempt, and succeeds reliably on the second. It's not a problem for me as it's only a test branch with all the test packages, but I though I'd give you a heads-up.
Further observations:
We were on mongoose ^6.6.5 and then upgraded to the latest, which didn't change anything
I can send you guys the yarn.lock files to get a delta if you want (preferrable wouldn't want to paste that here though))
Feel free to close this at any time. As said, it's more of an FYI than an actual problem for us currently
Steps to Reproduce
I'm just awaiting mongoose.connect(...)
Expected Behavior
mongoose.connection to not be undefined after connecting.