Losing extension when use FileReference download

Question

I need user download JPEG file from my app, however, when user change the file name the saved file will be downloaded without extension.

For Example: I am using File

Answer 1

I have the same problem and was not able to fix it until now. It seems it is a problem with flash + windows. :( sorry to inform but I did not found any fix.

If this can be called a workaround, is somehow to warn users and ask them to place also the extension when they rename the file.