Share intent from third-party apps fails on Android 16 / One UI 8 / Knox 3.12 (F-Droid & Play Store version)

I opened a github issue 10 days ago, I would love this feature works on my device…

### Steps to reproduce

1. Install latest Nextcloud app from F-Droid (after uninstalling Play Store version).

2. Grant all permissions: Access to all files (enabled via Settings > Privacy > Special app access), photos/videos, notifications, battery optimization disabled.

3. From any third-party app (e.g. Gallery, browser), tap Share > select Nextcloud.

4. Nothing happens: no upload dialog, no error message, share sheet closes silently.

Direct uploads via Nextcloud file picker work fine. Auto-upload also functional.

### Expected behaviour

Share intent should open Nextcloud upload dialog, allowing selection of target folder and immediate upload.

### Actual behaviour

Upload failure. No Internet connection.

### Android version

16

### Device brand and model

Samsung (One UI 8, Knox 3.12)

### Stock or custom OS?

Stock

### Nextcloud android app version

3.34.1

### Nextcloud server version

32.0.1

### Using a reverse proxy?

Yes

### Android logs

_No response_

### Server error logs

```bash

```

### Additional information

### Installation method

- F-Droid (latest version as of Nov 27, 2025)

- Previously tried Play Store version (same issue)

### Additional context

- Scoped Storage fully permitted, SAF paths configured.

- Works perfectly on iOS device with same Nextcloud server.

- Manual file browsing/upload within Nextcloud app succeeds.

- Tried: cache clear, reinstall, path changes (/storage/emulated/0/), Knox tweaks.

This blocks core share-to-cloud workflow. F-Droid was recommended as Play Store workaround due to Google permission revocation, but issue persists on Android 16 + Samsung Knox stack. [web:49][web:61]

**Related issues:** #3301, #15109 (Android 16), #14895 (F-Droid signature)