Why won't iCloud Contacts from iPhone sync on MacBook Pro

To Whom it May Concern,

Evidently there are about 10 billion reasons "contacts" on a MacBook pro might not sync up with iCloud, and therefore not on any other connected devices, i.e. iPhone, etc.

I know b/c I spent no less than 10 hours on the phone with AppleCare, over the course of about 4 different days, reboots, re-installs, settings changes, mass deletions, etc etc etc. All the while, I was convinced it might be something incredibly fundamental that no one else was thinking about.

It was working fine before I:

A. updated OS

B. got a replacement iPhone and migrated old phone

C. upgraded my iCloud storage (not enough room to back up old phone on MacBook pro but I digress)

D. merged and re-remerged (multiple times) the duplicated contacts

Well, nothing worked and we had to schedule yet another phone meeting. I decided to sniff around this morning - and...alas...wait for it...............

SAFARI SETTINGS/Websites for iCloud:

1. POP UP WINDOWS
2. CONTENT BLOCKERS

Yep. All I had to do was set both to "allow." Were they set to "allow" before? I have no idea. All I know is, this simple oft overlooked step solved the problem that hours upon hours of Tech support could not figure out.

Yes, of course, you might have an issue with your Apple ID, or a different setting, or a mysterious plist in a library I never heard of until yesterday. Or...you might just have to ALLOW iCloud to do its thing.

Good grief, I hope you don't go through what I did to correct this possibly simple glitch.

Good luck!

Check here -> If your iCloud Contacts, Calendars, or Reminders won’t sync

If your iCloud Contacts, Calendars, or Reminders won’t sync - Apple Support