It is installed by default with the latest Chrome update (version 37.x) (originally on Chrome 35 beta and not installed by default), and how Chrome uses the DirectWrite API for Windows to render the font.
If you want the old behavior to open chrome://flags/ and enable Disable DirectWrite .
This will disable the use of the experimental DirectWrite font rendering system.
Also, as noted in this bug report :
All this comes from DW, which considers the weight of a font as different variants of the same font, unlike GDI. Thus, Arial Black is considered Arial with a weight of 900 and which corresponds to the specified family.
So, if "Arial Black" returns to "Arial" with a weight of 900 and a weight of 900 in Arial, this is not the same "weight" as Arial Black, then you will see the difference in the rendered font.
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