The WP article says:
"" Millions of websites contain a string of computer code from Meta that compiles your web activity. It might capture the income you report to the government, your application for a student loan and your online shopping. ""
If I read that correctly then they are capturing all https web content you access in clear text and uploads it all to Meta? Then Meta
I thought the exploit was used to track where you visited, not the full data of each webpage.