Bad screenshot file extension

[deshack]

Bad screenshot file extension! File screenshot.png is not an actual JPG file. Detected type was : "image/png".

--- Want to back this issue? **[Post a bounty on it!](https://www.bountysource.com/issues/34303981-bad-screenshot-file-extension?utm_campaign=plugin&utm_content=tracker%2F972380&utm_medium=issues&utm_source=github)** We accept bounties via [Bountysource](https://www.bountysource.com/?utm_campaign=plugin&utm_content=tracker%2F972380&utm_medium=issues&utm_source=github).