To enable ENABLE MOD_PAGESPEED in WordPress using htaccess. Add the following code in your htaccess file located in WordPress root folder.
# ENABLE MOD_PAGESPEED START # COMBINE CSS, COMPRESS IMAGES, REMOVE HTML WHITE SPACE AND COMMENTS <IfModule pagespeed_module> ModPagespeed on ModPagespeedEnableFilters rewrite_css,combine_css ModPagespeedEnableFilters recompress_images ModPagespeedEnableFilters convert_png_to_jpeg,convert_jpeg_to_webp ModPagespeedEnableFilters collapse_whitespace,remove_comments </IfModule> # ENABLE MOD_PAGESPEED END
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