Screenshot transparency bug

Created by: S4K4YUME

Introduction

I'm opening this issue to give a more thorough overview of a recent bug that has been encountered, but unlike in #23 (closed) , this is something I feel we should address as it is not a 'possible feature' but a genuine bug.

Images

Below a couple of images in different pieces of software, giving insight into what is going on.

Tree in the viewport

Possible fix

As there are values on the pixels where they should be, but just the representation is inconsitent across applications and always wrong, ánd the correct color appears at the edges (probably due to anti-aliasing), I strongly suspect this to be an encoding issue.

One thing to perhaps consider is that, unlike many image-formats (such as EXR, RAW, TIF) which use an RGBA format, PNG uses RGB and transparency. Transparency != alpha.

I haven't looked at this further, but perhaps this is an angle to approach this from.