As soon as i loaded my test image i noticed the gradient was no longer smooth but it contained some vertical artifacts. I should point out that the gamma is set to default in Ubuntu: xgamma gamma 1.0
I also have Windblows 10 and OSX and there the gradient is smooth. However in Ubuntu it is brighter and contains vertical artifacts. And each time i take a screenshot, test image becomes brighter. This is driving me crazy.
Here is a screenshot from Ubuntu. Look into the black area and notice how an extra gamma is applied, reducing the amount of black compared to original. Also notice vertical artifact:

Notice how bright the image becomes after a couple of screenshots (a screenshot of a screenshot of a screenshot to be exact):

The test image in the last example has become stupidly bright indicating there is another layer of gamma control present in the display settings that is just hidden from access and is added to the previous gamma which was present in a screenshot.
Please keep in mind before you mention i should change gamma, this is all happening at gamma 1.0.
