Similar Projects
Other projects that aim to protect users from PDF exploits or privacy vulnerabilities.
Tktk. Source here.
A rust-based implementation of Dangerzone. Their homepage is available here.
MediaWiki software (the one Wikipedia runs on) converts PDF documents to images so that users visiting wikipedia don't run the risk of having their IP addressed leaked via an unsafe document viewer. They document PDF privacy risks here and the PDF converter implementation is available here.
As you can see on the picture below you, the software displays the PDF as a series of images and informs the users of the potential privacy risks of opening PDF documents directly.
The by default, this runs on the MediaWiki server but it can be moved to an external server via Shellbox (related presentation slides) with rasterization happening by yet another system Thumbor.
Arguable this is the predecessor of Dangerzone, but it focused more on safe redaction rather than santization of documents. The project is available here.