QGIS » QGIS Application

Using the same project as above, the picture attached is how it renders in 3.03 running on another system (Manjaro Linux). Again it is just the rasters that have been customised in Gimp, and the rasters as regular jpeg images view just fine in an image viewer on the same computer.

A new version of Gimp was recently released, and it's difficult to know if that has any bearing on this situation. However, creating a new project file and adding the same rasters to it results in a normal display instead of a garbled one.

So I just downloaded some new aerial photography from the internet and I open it in a 2.18 project and the same thing happens with the funny colours. So this also happens in 2.18 and happens with files that have not been altered by me in any way. I can tell you for a fact that the colours you can see in this screen shot attached are totally unnatural, the dark blue for the harbour is supposed to be ocean colour or blue-green, and the yellow buildings, you would find, are actually red.

Pretty much everything I can test with will show this problem.
2.18.17, 2.14.22 and a version of 2.99 going back 18 months.