A few more images to display the problem that was reported more than four years ago...
Since it has been such a long time from the first post, it is worth mentioning a few details from the past
The problem originated in Internet Explorer, MS Office 2013 and the modern Apps in Windows 8, as a result of Microsoft's new rendering engine. It was more annoying in IE and Office, as the "metro" apps had usually larger fonts and nobody cared so much about them in the first place...
Some users claimed that the new engine was grayscale (or more correctly monochromatic or single-colored) and that was the root of the problem. It was said that the classic "Microsoft Clear-Type" engine that combined neighboring pixels of different colors was not efficient in displays that changed orientation (eg. tablets). On the contrast, the new rendering engine with only one-color rendering (the same of the text) would work better with rotating screens.
Two things didn't make sense to me from this statement: a) Why was then "clear-type" still utilized in other areas of the UI and where was the problem with it? I had a Windows tablet and there seemed to be no problem with font rendering and rotation (in windows explorer, for example). b) Up to closer look (zooming in), it was not the one-color thing causing the issue but the rendering itself that was distributing the text in a non-optimal way in the pixels.
Both observations are somewhat verified by the above images from Windows 10 (Chrome VS Edge). a) Apparently single-color rendering has been dropped (you can see more colors when zoomed in in the pixels) and "clear-type" is still in use in Windows (see file explorer, control panel etc). b) The text is still blurry even with the modern, now multi-colored rendering engine (see how 15 consecutive i's have been rendered in an absurd way in MS Edge vs Chrome).