FolderListModel not refreshed on changed file size

When a list control is bound to a FolderListModel and displays the file size, the latter is not updated when the underlying file has its size changed - for example, when recording audio. To reproduce:
1. Open and start the attached project;
2. Push the "Record" button - you'll see an entry appearing in the list displaying 3014 or similar;
3. Leave it running for a few seconds;
4. Press the button again (which now says "Stop");
5. You'll see that the application still displays 3104;
6. Exit the app and start it again - since the FolderListModel reads from the file system on start, you'll now see a larger number depending on how much time you left the recorder running.

If it's too time-consuming or even impossible to automatically refresh the FolderListModel in such cases, please at least add a refresh-like method to call manually. Besides, any workarounds other than rebinding the whole list are appreciated.