Safari won't load pages after system restore I hope someone can advise please...

A few days ago I had to restore my whole system from Time Machine backup after a power outage stopped my Mac from booting up.  Everything seems fine, except for Safari.

Safari now won't load any web pages, it just shows a message at the top: "this webpage was reloaded because a problem occurred".  Other browsers are fine.

My MacOS is High Sierra 10.13.6 

Safari version is 12.0.3

I have read other pages that suggest that maybe when I was restoring, that the newest version of Safari might have downloaded via "automatic updates" from the App store, but I don't know (a) what version of Safari I had before, and (b) whether Safari 12.0.3 is meant to be OK with High Sierra 10.13.6?

Any clues or advice welcome!
This could be a problem with the wrong version of Safari, or it could be a problem with its cache or preference file.

Start by deleting the cache folder, located here:

~/Library/Caches/com.apple.Safari/


If that doesn't work, delete the preference file here:

/Users/sklein/Library/Preferences/com.apple.Safari.plist


If the problem persists, delete Safari (by dragging it to the Trash), then reinstall macOS High Sierra from Recovery.

The reinstall will take a while, but you won't lose any apps or data.