Large PDF’s crash Nextcloud

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Steps to reproduce

1. Open the Nextcloud iOS app and navigate to any large PDF file (reproduces with multiple different PDFs in the 20MB+ range).
2. Tap the PDF to open it in the in-app viewer.
3. Scroll through the document continuously.

Expected behaviour

The PDF viewer should remain stable and allow continuous scrolling/navigation through large documents without crashing.

Actual behaviour

The PDF opens and renders correctly. After scrolling for under a minute, the Nextcloud app crashes and is dismissed back to the iOS home screen. This is reproducible across multiple different large PDFs, so it does not appear to be a file-specific issue — it looks size/memory related. Smaller PDFs do not exhibit the crash.

Logs

If applicable, you can post the iOS app or server logs (removing any sensitive information).

Reasoning or why should it be changed/implemented?

Viewing PDFs is a core use case for the Nextcloud iOS app, and large PDFs (manuals, scanned documents, books) are common. The viewer should handle them without crashing, or fall back to paged/streaming rendering if the document exceeds available memory.

Environment data

iOS version: iPad OS 26.4.1
iPad model: iPad Pro 13 M4
Nextcloud iOS app version: 33.0.8.1
Server operating system: 32.0.8
Affected PDFs: Multiple large, both text-based and image-heavy.

Start at the Nextcloud iOS app’s in-app PDF viewer and reproduce the crash with a 20MB+ PDF while scrolling continuously. Compare behavior with smaller, text-based, and image-heavy PDFs, and inspect the iOS app logs if available. Done means large PDFs remain usable without crashing.