Safe Settings for Google Pagespeed Module

    #Head
    ModPagespeedEnableFilters add_head
    ModPagespeedEnableFilters combine_heads
    #HTML
    ModPagespeedEnableFilters remove_quotes
    ModPagespeedEnableFilters collapse_whitespace
    ModPagespeedEnableFilters elide_attributes
    ModPagespeedEnableFilters remove_comments
    #Images
    ModPagespeedEnableFilters rewrite_images
    ModPagespeedEnableFilters insert_img_dimensions
    ##ModPagespeedEnableFilters convert_gif_to_png
    ModPagespeedEnableFilters convert_png_to_jpeg
    ModPagespeedEnableFilters convert_jpeg_to_progressive
    ModPagespeedEnableFilters jpeg_subsampling
    ModPagespeedEnableFilters recompress_jpeg
    ##ModPagespeedEnableFilters recompress_png
    ModPagespeedEnableFilters recompress_webp
    ModPagespeedEnableFilters strip_image_color_profile
    ModPagespeedEnableFilters strip_image_meta_data
    ModPagespeedEnableFilters sprite_images
    ModPagespeedEnableFilters lazyload_images
    #CSS
    ModPagespeedEnableFilters rewrite_css
    ModPagespeedEnableFilters move_css_above_scripts
    ModPagespeedEnableFilters outline_css
    ModPagespeedEnableFilters rewrite_css
    ModPagespeedEnableFilters inline_css
    ModPagespeedEnableFilters combine_css
    ModPagespeedEnableFilters move_css_to_head
    #JavaScript
    ModPagespeedEnableFilters rewrite_javascript
    ModPagespeedEnableFilters defer_javascript
    ModPagespeedEnableFilters inline_javascript
    ModPagespeedEnableFilters outline_javascript
    #Cache
    ModPagespeedEnableFilters extend_cache
    #DNS
    ModPagespeedEnableFilters insert_dns_prefetch