I am aware some PDF’s transmit information (IP address etc.) via the internet when they are opened. I have got into the habit of using Foxit to prevent this.
Does DevonThink allow information transmission when a PDF is opened?
I can imagine how it’s possible that something inside a PDF could be coerced to transmit out into the internet, but I’m unaware of any PDF reader that proactively prevents that. I looked at the Foxit web site and can’t find any reference to that as a feature.
Could you please give me, for my own education, the Foxit URL for their description of what they do?
There are a few companies that add tracking to PDF’s. Publishers regularly track PDFs for example academic research papers, legal documents, etc and there are a number of companies that perform this service for example:
Do you have more details on this? Acrobat overtly offers a tracking function (e.g. so one could see who has signed a document, who still needs to be reminded to do so, etc.), but I can’t find any obvious way to deactivate what I understand you to be describing, which would be more along the lines of a generic tracking pixel or similar.
Using Little Snitch to block these connections is of course possible, but since Devon has web browser capabilities I allowed ports 80 and 443, which means these connection blocks have to be set up proactively as global rules.
Searching my blocklist subscriptions (from https://rulegroups.com) revealed that these trackers aren’t part of them.
On iOS, I use AdGuard with DNS based filters from Energized. Looking through Energized’s flagship unified list with 1,3 million domain blocks also reveals that these trackers aren’t included. Neither does https://oisd.nl include them.