File extention lost

### App version

v2.2.1 

### Android version

10

### Describe the bug

When transferring an GPX file from windows to android, the file extension is lost. It is stored without extension.

### Steps to reproduce the bug

Send an gpx file to android via pairdrop.net (maybe also snapdrop)

### Stacktrace

_No response_

### Screenshots and additional context

_No response_