Update: Here is the FireFox version.
The result of using this extension for the last week has been a pleasanter web experience: a lot of sites look crisper, more like reading a book printed with high quality ink on high quality acid-free paper. I miss it on my phone since mobile Chrome doesn't support extensions (I am tempted to switch to a mobile browser that does support extensions, but haven't done so yet).
Eventually, if there is any actual interest in the extension from people other than myself, I may add some per-site options in case some site is broken by this.