Contacts app pixelated

Contacts is part of the system so you'd have to reinstall the system to get a new Contact app.

The fact that Contacts works as expected in another user account means there's someitng in your account that's causing the problem.

With that in mind download and run Etrecheck. Etrecheck is a diagnostic tool that was developed by one of the most respected users here in the ASC and recommended by Apple Support  to provide a snapshot of the system and help identify the more obvious culprits that can adversely affect a Mac's performance.

Copy the report

and use the Additional Text button to include the report in your reply.

IMPORTANT:

Before running Etrecheck assign Full Disk Access to Etrecheck in the Etrecheck's Privacy preference pane so that it can get additional information from the Console and log files for the report:

Also click and read the About info to further permit full disk access.

Then we can examine the report and see if we can determine what might be causing the problem.

I see what probably is causing or contributing to your problem, two totally unnecessary anti-virus apps: Kaspersky, Avast and CCleaner. There is no reason to ever install or run any 3rd party "cleaning", "optimizing", "speed-up", anti-virus, VPN or security apps on your Mac.  This user tip describes what you need to know and do in order to protect your Mac: Effective defenses against malware and other threats - Apple Community.  Also unless you're using a true VPN tunnel, such as between you and your employer's or bank's servers, they are useless. Public VPN's are anything but private.  

Uninstall both of them according to the developer's instructions. Then you can check to see if you've removed all of the supporting files by downloading and running Find Any File to search for any files with the application's name  and the developer's name in the file name.  For the mentioned software you'd do the following search(es): 

1 - Name contains avast

2 - Name contains kaspersky

3 - Name contains ccleaner

Any files that are found can be dragged from the search results window to the Desktop or Trash bin in the Dock for deletion.

FAF can search areas that Spotlight can't like invisible folders, system folders and packages.  

You also have BitTorrent installed. Sites that use BitTorrent for download are more likely to include adware/maleware with the installers. I'd not use it and only get software directly from developer's website.

Hi there RoachUnited,

We understand you're experiencing an issue with the Contacts app being blurry on your Mac, and you've done some great troubleshooting steps so far! We'd like to see if we can assist.

Next, give any remaining steps here a try: If an app on your Mac stops responding, closes unexpectedly, or won’t open

Also, to determine if the issue is user-specific or system-wide, create a new user account and test for the issue there: Set up users, guests, and groups on Mac

Cheers!

RoachUnited,

Thanks for giving that step a try, and keeping us updated.

If you sync your contacts with an account, such as Gmail, iCloud, or Outlook, it may not be unusual for a loading bar to appear when connecting to the Internet for the data to sync.

Since the issue only occurs in your new user account, this indicates it's related to preferences or data in your account. To see if it's related to a login item, remove all of your login items, and try restarting your Mac again: Change Users & Groups Login Items preferences on Mac

Thanks!

Boot into Safe Mode by booting with the Shift key held down and check there to see if the problem persists.  Reboot normally and test again.

NOTE: Safe Mode boot can take up to 10 minutes as it's doing the following; 

• Verifies your startup disk and attempts to repair directory issues, if needed

• Loads only required kernel extensions (prevents 3rd party kernel/extensions from loading)

• Prevents Startup Items and Login Items from opening automatically

• Disables user-installed fonts 

• Deletes font caches, kernel cache, and other system cache files

RoachUnited,

We appreciate you sharing those details.

If the issue persists after updating to macOS Big Sur 11.1, reach out to look into this further here: Get Support

Take care.