Trust, but verify. Especially FB.
I see a lot of comments about a paid service using tracking pixels. I understand the backlash but this is also how companies that are taking your hard earned money improve and iterate on their products. I know people don’t like tracking but usage analytics are invaluable to improving the product. There’s only so much customer engagement you can do, and often that leaves really unexpected outcomes in the dark (if you asked most customers, they’d ask for a faster horse).
The issue here is that Backblaze injected untrusted code into their core product which by its very nature is extremely sensitive. I’m not really sure what they were thinking. Rolling your own tracking is a pain, but some security contexts demand it.