Blank Facebook page

Read If Safari on Mac doesn't open a webpage or isn't working as expected. The Facebook dot com website works on the Mac I happen to be using at the moment, and it is using the latest version of Safari available for High Sierra, so that suggests it should work even with an older Mac:

It's working for me as well.

I can only speculate, which will not help to solve your problem. Follow those Apple Support document's recommendations.

Running the same OS as above and have just encountered the same issue. Have tried all the standard protocols to correct the situation to no avail. Stumped.

I've the same problem running High Sierra 10.13.6 on an old iMac this week Facebook went blank and couldn't get it to load. It works fine on Chrome.

It's working today. Nothing that I did. I assume it was a FB issue of some kind.