I can’t find anything resembling greenish even after I zoomed that 600% and drew a pure white rectangle over the bottom half. Just gray and white. Could it be something in your screen’s settings?
Same here; just looks white to me.
Room lighting can also alter how on-screen colours appear to the eye.
It is white, Nick. Check your monitor settings and/or the monitor’s settings in Plasma’s System Settings.
Or maybe call someone to take a look at your screen (i mean literally take a look at the screen behind your shoulder) and if they say it is white then it’s not the settings but color blindness. 30% of the people have variations in this regard anyway, and you are not exactly young and completely healthy anymore so it’s something to check.
If this is the case the doctor has to mesure the exact parameters because the variants are countless. Pretty sure plasma has some setting to compensate it it just needs the numbers (i think there were sliders from 0 to 100 for the different colors). Then all the other people in the room will see greenish but you will see white and that is all that matters 
Nick, just some further thoughts on room lighting conditions: it is well worth experimenting with that.
As a lighting enthusiast and (former) experimenter, I can say that the types of light (colour temperature, spectral output) can have a massive effect on how well one can see a monitor.
Also, surrounding colours on the screen itself may be an influence.
For example, I have, for a very long time, used a clear mercury vapour lamp in a modified Ikea uplighter in my loft space and this doesn’t seem to reflect off monitor and TV screens to any significantly noticeable degree, whereas if I put a coated lamp in it washes out the displays, making them hard to see (or even worse, high-pressure sodium).
The clue here is, maybe using higher colour temperature lighting might well help with these visibility issues. There’s only one way to find that out.
Strange, in Mozilla they look fine. I have A KTC miniLED.
Damn straight.
That 30% would probably think your green bug avatar was red.
Um, it is red. 
This thread is starting to grow a pretty large amount of off-topic branches. 
wags finger