My .htaccess file has the following text:
Spoiler
# Images
ExpiresByType image/jpeg "access plus 1 year"
ExpiresByType image/gif "access plus 1 year"
ExpiresByType image/png "access plus 1 year"
ExpiresByType image/webp "access plus 1 year"
ExpiresByType image/svg+xml "access plus 1 year"
ExpiresByType image/x-icon "access plus 1 year"
# Video
ExpiresByType video/mp4 "access plus 1 year"
ExpiresByType video/mpeg "access plus 1 year"
# CSS, JavaScript
ExpiresByType text/css "access plus 1 month"
ExpiresByType text/javascript "access plus 1 month"
ExpiresByType application/javascript "access plus 1 month"
# Others
ExpiresByType application/pdf "access plus 1 month"
ExpiresByType application/x-shockwave-flash "access plus 1 month"
</IfModule>
######### Piepcomp SETTING - START ##########
Options All -Indexes
# Disable ETags
<IfModule mod_headers.c>
Header unset ETag
Header set Connection keep-alive
</IfModule>
FileETag None
############## MaxCDN Fix #############
<IfModule mod_headers.c>
<FilesMatch "\.(ttf|ttc|otf|eot|woff|woff2|font.css|css|js)$">
Header set Access-Control-Allow-Origin "*"
</FilesMatch>
</IfModule>
########### REDIRECT TRAFFIC TO HTTPS ############
# RewriteEngine On
# RewriteCond %{HTTPS} off
# RewriteRule (.*) https://%{HTTP_HOST}%{REQUEST_URI} [R=301,L]
############ SECURITY ###########
<FilesMatch "\.(md|exe|sh|bak|inc|pot|po|mo|log|sql)$">
Order allow,deny
Deny from all
</FilesMatch>
<Files robots.txt>
Allow from all
</Files>
############## CACHING-GZIP ############
<IfModule mod_expires.c>
ExpiresActive On
ExpiresDefault A2592000
<FilesMatch "\.(txt|xml|js)$">
ExpiresDefault A2592000
</FilesMatch>
<FilesMatch "\.(css)$">
ExpiresDefault A2592000
</FilesMatch>
<FilesMatch "\.(flv|ico|pdf|avi|mov|ppt|doc|mp3|wmv|wav|mp4|m4v|ogg|webm|aac)$">
ExpiresDefault A2592000
</FilesMatch>
<FilesMatch "\.(jpg|jpeg|png|gif|swf|webp)$">
ExpiresDefault A2592000
</FilesMatch>
</IfModule>
<IfModule mod_headers.c>
<FilesMatch "\.(txt|xml|js)$">
Header set Cache-Control "max-age=2592000"
</FilesMatch>
<FilesMatch "\.(css)$">
Header set Cache-Control "max-age=2592000"
</FilesMatch>
<FilesMatch "\.(flv|ico|pdf|avi|mov|ppt|doc|mp3|wmv|wav|mp4|m4v|ogg|webm|aac)$">
Header set Cache-Control "max-age=2592000"
</FilesMatch>
<FilesMatch "\.(jpg|jpeg|png|gif|swf|webp)$">
Header set Cache-Control "max-age=2592000"
</FilesMatch>
</IfModule>
<IfModule mod_deflate.c>
<IfModule mod_setenvif.c>
<IfModule mod_headers.c>
SetEnvIfNoCase ^(Accept-EncodXng|X-cept-Encoding|X{15}|~{15}|-{15})$ ^((gzip|deflate)\s*,?\s*)+|[X~-]{4,13}$ HAVE_Accept-Encoding
RequestHeader append Accept-Encoding "gzip,deflate" env=HAVE_Accept-Encoding
</IfModule>
</IfModule>
<IfModule mod_filter.c>
AddOutputFilterByType DEFLATE "application/atom+xml" \
"application/javascript" \
"application/json" \
"application/ld+json" \
"application/manifest+json" \
"application/rdf+xml" \
"application/rss+xml" \
"application/schema+json" \
"application/vnd.geo+json" \
"application/vnd.ms-fontobject" \
"application/x-font-ttf" \
"application/x-javascript" \
"application/x-web-app-manifest+json" \
"application/xhtml+xml" \
"application/xml" \
"font/eot" \
"font/opentype" \
"image/bmp" \
"image/svg+xml" \
"image/vnd.microsoft.icon" \
"image/x-icon" \
"text/cache-manifest" \
"text/css" \
"text/html" \
"text/javascript" \
"text/plain" \
"text/vcard" \
"text/vnd.rim.location.xloc" \
"text/vtt" \
"text/x-component" \
"text/x-cross-domain-policy" \
"text/xml"
</IfModule>
<IfModule mod_mime.c>
AddEncoding gzip svgz
</IfModule>
</IfModule>
######### Piepcomp SETTING END ############
<IfModule mod_rewrite.c>
RewriteEngine On
RewriteBase /
RewriteRule ^index\.php$ - [L]
RewriteCond %{REQUEST_FILENAME} !-f
RewriteCond %{REQUEST_FILENAME} !-d
RewriteRule . /index.php [L]
</IfModule>
<IfModule mod_expires.c>
ExpiresActive On
ExpiresDefault A2592000
<FilesMatch "\.(txt|xml|js)$">
ExpiresDefault A2592000
</FilesMatch>
<FilesMatch "\.(css)$">
ExpiresDefault A2592000
</FilesMatch>
<FilesMatch "\.(flv|ico|pdf|avi|mov|ppt|doc|mp3|wmv|wav|mp4|m4v|ogg|webm|aac)$">
ExpiresDefault A2592000
</FilesMatch>
<FilesMatch "\.(jpg|jpeg|png|gif|swf|webp)$">
ExpiresDefault A2592000
</FilesMatch>
</IfModule>
<IfModule mod_headers.c>
<FilesMatch "\.(txt|xml|js)$">
Header set Cache-Control "max-age=2592000"
</FilesMatch>
<FilesMatch "\.(css)$">
Header set Cache-Control "max-age=2592000"
</FilesMatch>
<FilesMatch "\.(flv|ico|pdf|avi|mov|ppt|doc|mp3|wmv|wav|mp4|m4v|ogg|webm|aac)$">
Header set Cache-Control "max-age=2592000"
</FilesMatch>
<FilesMatch "\.(jpg|jpeg|png|gif|swf|webp)$">
Header set Cache-Control "max-age=2592000"
</FilesMatch>
</IfModule>
<IfModule mod_deflate.c>
<IfModule mod_setenvif.c>
<IfModule mod_headers.c>
SetEnvIfNoCase ^(Accept-EncodXng|X-cept-Encoding|X{15}|~{15}|-{15})$ ^((gzip|deflate)\s*,?\s*)+|[X~-]{4,13}$ HAVE_Accept-Encoding
RequestHeader append Accept-Encoding "gzip,deflate" env=HAVE_Accept-Encoding
</IfModule>
</IfModule>
<IfModule mod_filter.c>
AddOutputFilterByType DEFLATE "application/atom+xml" \
"application/javascript" \
"application/json" \
"application/ld+json" \
"application/manifest+json" \
"application/rdf+xml" \
"application/rss+xml" \
"application/schema+json" \
"application/vnd.geo+json" \
"application/vnd.ms-fontobject" \
"application/x-font-ttf" \
"application/x-javascript" \
"application/x-web-app-manifest+json" \
"application/xhtml+xml" \
"application/xml" \
"font/eot" \
"font/opentype" \
"image/bmp" \
"image/svg+xml" \
"image/vnd.microsoft.icon" \
"image/x-icon" \
"text/cache-manifest" \
"text/css" \
"text/html" \
"text/javascript" \
"text/plain" \
"text/vcard" \
"text/vnd.rim.location.xloc" \
"text/vtt" \
"text/x-component" \
"text/x-cross-domain-policy" \
"text/xml"
</IfModule>
<IfModule mod_mime.c>
AddEncoding gzip svgz
</IfModule>
</IfModule>
Also I have enabled pagecachin on the file sytem via src >config.php
Spoiler
$config['pageCache']['enabled'] = true;
$config['cache']['context']['page']['provider'] = 'Filesystem';
$config['cache']['context']['page']['config'] = ['directory' => '/your domain/file_cache_xenforo'];
Both immediately bettered my GTMetrics result:
Fully Loaded time: 5.0s, Total Page Size: 649KB, Requests: 38
gtmetrix.com