How to Check and Make Sure PDFs Have Different Fingerprints
For each PDF you want to check:
1. Open the PDF in Chrome
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2. Activate the Hypothesis extension
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3. Click the “<” tab to open the sidebar. Then click on “?” and then “About this version”
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4. The PDF Fingerprint is towards the bottom, marked “Fingerprint”.
The PDF fingerprint is a long string of numbers and letters in the Console, it should be different for each version of the PDF you’ve made.