Enable mod_pagespeed https://technumero.com/increase-page-speed-using-htaccess-wordpress/

.htaccess

#
# Paste the following code into your .Htaccess file 
#


# TN – 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>
# TN – ENABLE MOD PAGESPEED END