PWA on Android crashes when attaching video/audio files via file picker (JPEG/PDF work fine)

Environment

· Nextcloud version: 34.0.1
· Nextcloud Forms version: 5.3.4
· Client: Android PWA (installed via "Add to Home Screen" from Google Chrome)
· Android version: 12 (MIUI 14)
· Android System WebView version: 150.0.7871.46
· Device: XIAOMI Poco x3 nfc

Steps to reproduce

1. Open a form with file upload in the PWA
2. Tap upload and select a video file (.mp4)
3. Test with files of different sizes

Actual behavior

· 2.06 MB video → uploaded successfully
· 2.42 MB video → crash / error
· JPEG images up to 8 MB → uploaded successfully regardless of size
· The crash happens immediately on file selection, before network upload

Root cause (assumed)
Android WebView's file picker has a fixed IPC buffer (~2 MiB) when transferring selected files to the PWA. For video/audio, WebView likely tries to read metadata or generate a thumbnail within this limited buffer. Images are handled differently by the system media provider, bypassing this limit. This is a known class of WebView limitation, and a workaround on the Forms side is needed (e.g., chunked file reading).

No file or test path is named. Start by reproducing the upload flow in the Android PWA with audio and video files around the reported size threshold, then trace the file-upload handling; done means larger media selections no longer crash while JPEG and PDF uploads continue to work.