Contacts keep crashing. What are my options? Using unrooted vanilla Android 8.1. The default Contacts app always crashes on start.  


I have made sure to update to the latest version: 2.8.4.201036949
I have rebooted the device and installed all other available updates
I have cleared the cache for Contacts
I have tried to sideload the apk but got "INSTALL_FAILED_VERSION_DOWNGRADE" error
I have used adb backup but the backup is only 1kb when the app's data is over 10mb on the phone so I'm worried that the backup doesn't include all my contacts


Interestingly, other applications that rely on Contacts such as Phone or Signal Messenger can see these contacts but I cannot create or modify contacts.

I am hoping for ideas on how to get out of this conundrum without losing my contacts.  I don't sync contacts with Google (would like to keep it that way) and wouldn't want to do it with another party either. Perhaps running in some kind of "Safe Mode" or using another app to read and copy contacts and create a vcf file that I can import from Contacts once I've uninstalled/reinstalled it
I found a 3rd party Contacts app that could read Android contacts and save them as a .vcf file.  The .vcf file could then later be imported into the default Contacts app once I get things sorted.  The app is called Contacts VCF

As for my crash problem, I went to Settings >> Applications >> Contact and force closed the Contacts app.  Then from the same screen I tapped "Disabled" and confirmed that data would be lost.  This reset the app to its initial state (before all the updates since I started using it).

I then went to the app's page in the Google Play Store and clicked Enable to turn the app back on, then Update to bring it current.

Now the app works again; I imported the .vcf file that I had exported in the first step above to restore my contacts.