PDF fullscreen Presentation Mode doesn't letterbox
- Open a PDF file in a new tab so it opens in the browser's internal PDF viewer. Here's one. https://gitweb.torproject.org/company/policies.git/plain/corpdocs/IRS-Determination-Letter.pdf
- Click the 4-outward-arrows (fullscreen?) icon on the PDF toolbar. Its tooltip when you hover on it says, "Switch to Presentation Mode"
- Observe that Presentation Mode is not letterboxed.
PDF Presentation Mode is distinct from browser full screen (F11 key) and from maximize.
Is this exploitable at all? Is the internal PDF API fingerprintable? Tor Browser warns when downloading to not open files in external viewers that could circumvent Tor.
Similar vectors:
- #32713 (moved), Letterboxing doesn't work when fullscreening videos
- #12609 (moved), HTML5 fullscreen API makes TB fingerprintable
Inspired by: