Incorrect file type for generated image

[kounelios13]

Hello. Congratulations for your book. I tried the wasm application and noticed the following bug: When I upload a PNG image the final result will have a JPEG file extension. On linux if you try to open it without renaming the file extension you get an error

[preslavrachev]

Thanks for letting me know. I will check the code. I made the uploader explicitly ask for JPGs only, to avoid having to type-check the incoming image.