Passport.js: Serialization issue with local login strategy - node.js

Question

I'm having trouble authenticating a small passport.js example project when I switch over to mongodb instead of a local array.
MongoDB is able to connect and add users from a form on the home page. On login however, there are problems.
Not sure if this matters but on the /login page onload I see 2 red errors in the browser console:
Unchecked runtime.lastError: Could not establish connection. Receiving end does not exist.
login:1
Unchecked runtime.lastError: The message port closed before a response was received.
I put a log statement in the relevant route handler. It does not reach or log to the console.
app.post('/login', function sendUserRecordToAxiosOrRedirect(req, res, next) {
passport.authenticate('local', function controlErrorsOrSuccess(error, userRecord, info) {
console.log('inside pp.auth callback');
if (error) return next(error);
if (userRecord == false) return res.json ({ "error" : "Invalid Username" });
if (userRecord) {
console.log('---- User Found: INFO --------');
console.log(info);
res.redirect('/')
}
})
});
From the above I suspected something is awry with the Strategy I give to passport. The log statement in this one doesn't fire either:
passport.use(new Strategy(
function(username, password, done) {
console.log('inside Strategy');
db.users.findInDatabaseByUsername(username, function (error, userRecord) {
if (error) return done(error);
if (userRecord == false) return done(null, false); // no error, no userRecord
if (userRecord.password !== password) return done(null, false);
return done(null, userRecord);
})
}
));
Since I altered my serialization functions to search the database instead of an array I suspect the problem may lie here. Neither of the log statements here fire either:
const passUserIdOnlyToACallback = function(userRecord, callbackFunction) {
console.log("serializing...");
callbackFunction(null, userRecord.id);
};
passport.serializeUser(passUserIdOnlyToACallback);
function passUserRecordToCallbackById(userId, verifyCallback) {
db.users.findInDatabaseById(userId, function(error, userRecord) {
console.log("deserializing...");
if (error) return verifyCallback(error);
verifyCallback(null, userRecord)
})
}
passport.deserializeUser(passUserRecordToCallbackById);
Everything was working fine initially with the local array code, so my alterations broke something. Does anyone see the error?