FVM HTACCESS

FVM does not add anything to .htaccess.
What helps speed on my server (a lot), is adding good directives for gzip and brotli compression, both for precompressed and on-the-fly compression. If you feel comfortable adding these to htaccess, reply here and I will post them. Not sure if this will help in your case, but I think this is the most overlooked tweak on WordPress servers.

Ok Angus, you can try adding problem CSS/JS to “Ignore List” on the “Pro” tab.
As for the gzip and brotli compression, see below for my crafted htaccess directives which are the best I have seen!
Add them to htaccess before the WordPress default and caching directives.
These directives (incl cache control) will serve compressed css,js and html files, in this order:
– Precompressed Brotli (if file exists and clients accepts)
– Precompressed Gzip (if file exists and clients accepts)
– On-the-fly Compressed Brotli (if server enabled and clients accepts)
– On-the-fly Compressed Gzip (if server enabled and clients accepts)
– Uncompressed (if client does not accept compressed file format)

# ===== BEGIN BROTLI =====
# BROTLI Dynamic - Server Generated on-the-fly
<ifmodule mod_brotli.c>
    AddOutputFilterByType BROTLI_COMPRESS text/html text/css text/javascript text/plain application/json application/javascript application/x-javascript text/xml application/xml application/xml+rss
</ifmodule>
<IfModule mod_headers.c>
# BROTLI Static - Precompressed
# Serve Brotli compressed HTML, CSS and JS files if they exist and the client accepts brotli.
    RewriteCond "%{HTTP:Accept-encoding}" "br"
    RewriteCond "%{REQUEST_FILENAME}\.br" "-s"
    RewriteRule "^(.*)\.(html|js|css)"              "$1\.$2\.br" [QSA]
# Serve correct content types, and prevent double compression.
    RewriteRule "\.html\.br$"  "-" [T=text/html,E=no-brotli:1,E=no-gzip:1]
    RewriteRule "\.css\.br$" "-" [T=text/css,E=no-brotli:1,E=no-gzip:1]
    RewriteRule "\.js\.br$"  "-" [T=text/javascript,E=no-brotli:1,E=no-gzip:1]
  <FilesMatch "(\.html\.br|\.js\.br|\.css\.br)$">
# Serve correct encoding type.
    Header append Content-Encoding br
# Force proxies to cache compressed/uncompressed files separately
    Header append Vary Accept-Encoding
  </FilesMatch>
  <FilesMatch "(\.js\.br|\.css\.br)$">
# Cache Control and Enable CORS
    ExpiresActive On
    ExpiresDefault  "access plus 1 month"
    Header set Cache-Control "public, immutable, max-age=2628000, s-maxage=2628000"
    Header set Access-Control-Allow-Origin "*"
  </FilesMatch>
</IfModule>
# ===== END BROTLI =====

# ===== BEGIN GZIP =====
# GZIP Dynamic - Server Generated on-the-fly
<ifmodule mod_deflate.c>
    AddOutputFilterByType DEFLATE text/html text/css text/javascript text/plain application/json application/javascript application/x-javascript text/xml application/xml application/xml+rss
</ifmodule>
# GZIP Static - Precompressed
<IfModule mod_headers.c>
# Serve gzip compressed CSS and JS files if they exist and the client accepts gzip.
    RewriteCond "%{HTTP:Accept-encoding}" "gzip" [OR]
    RewriteCond "%{HTTP:Accept-encoding}" "deflate"
    RewriteCond "%{REQUEST_FILENAME}\.gz" -s
    RewriteRule "^(.*)\.(html|js|css)"              "$1\.$2\.gz" [QSA]
# Serve correct content types, and prevent double compression.
    RewriteRule "\.html\.gz$" "-" [T=text/html,E=no-gzip:1,E=no-brotli:1]
    RewriteRule "\.css\.gz$" "-" [T=text/css,E=no-gzip:1,E=no-brotli:1]
    RewriteRule "\.js\.gz$" "-" [T=text/javascript,E=no-gzip:1,E=no-brotli:1]
  <FilesMatch "(\.html\.gz|\.js\.gz|\.css\.gz)$">
# Serve correct encoding type.
    Header append Content-Encoding gzip
# Force proxies to cache compressed/uncompressed files separately
    Header append Vary Accept-Encoding
  </FilesMatch>
  <FilesMatch "(\.js\.gz|\.css\.gz)$">
# Cache Control and Enable CORS
    ExpiresActive On
    ExpiresDefault  "access plus 1 month"
    Header set Cache-Control "public, immutable, max-age=2628000, s-maxage=2628000"
    Header set Access-Control-Allow-Origin "*"
  </FilesMatch>
</IfModule>
# ===== END GZIP =====