mod_pagespeed is an open-source Apache module that automatically optimizes web pages and resources on them.
Windows-1251 (a.k.a. code page CP1251) is a popular 8-bit character encoding, designed to cover languages that use the Cyrillic script such as Russian, Bulgarian, Serbian Cyrillic and other languages.
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The http-equiv attribute provides an HTTP header for the information/value of the content attribute. The http-equiv attribute can be used to simulate an HTTP response header.