diff --git a/config/environments/production.rb b/config/environments/production.rb
index b42f78b14ea..7e164aa3834 100644
--- a/config/environments/production.rb
+++ b/config/environments/production.rb
@@ -15,22 +15,18 @@ Rails.application.configure do
   config.eager_load = true
 
   # Full error reports are disabled and caching is turned on.
-  config.consider_all_requests_local       = false
+  config.consider_all_requests_local = false
   config.action_controller.perform_caching = true
-  config.action_controller.asset_host      = ENV['CDN_HOST'] if ENV['CDN_HOST'].present?
 
   # Ensures that a master key has been made available in ENV["RAILS_MASTER_KEY"], config/master.key, or an environment
   # key such as config/credentials/production.key. This key is used to decrypt credentials (and other encrypted files).
   # config.require_master_key = true
 
-  # Compress CSS using a preprocessor.
-  # config.assets.css_compressor = :sass
-
-  # Do not fallback to assets pipeline if a precompiled asset is missed.
-  config.assets.compile = false
+  # Disable serving static files from `public/`, relying on NGINX/Apache to do so instead.
+  # config.public_file_server.enabled = false
 
   # Enable serving of images, stylesheets, and JavaScripts from an asset server.
-  # config.asset_host = "http://assets.example.com"
+  config.asset_host = ENV['CDN_HOST'] if ENV['CDN_HOST'].present?
 
   # Specifies the header that your server uses for sending files.
   config.action_dispatch.x_sendfile_header = ENV['SENDFILE_HEADER'] if ENV['SENDFILE_HEADER'].present?
@@ -40,27 +36,37 @@ Rails.application.configure do
   # Allow to specify public IP of reverse proxy if it's needed
   config.action_dispatch.trusted_proxies = ENV['TRUSTED_PROXY_IP'].split(/(?:\s*,\s*|\s+)/).map { |item| IPAddr.new(item) } if ENV['TRUSTED_PROXY_IP'].present?
 
+  # Assume all access to the app is happening through a SSL-terminating reverse proxy.
+  # Can be used together with config.force_ssl for Strict-Transport-Security and secure cookies.
+  # config.assume_ssl = true
+
   # Force all access to the app over SSL, use Strict-Transport-Security, and use secure cookies.
   config.force_ssl = true
+  # Skip http-to-https redirect for the default health check endpoint.
   config.ssl_options = {
     redirect: {
       exclude: ->(request) { request.path.start_with?('/health') || request.headers['Host'].end_with?('.onion') || request.headers['Host'].end_with?('.i2p') },
     },
   }
 
-  # Info include generic and useful information about system operation, but avoids logging too much
-  # information to avoid inadvertent exposure of personally identifiable information (PII). If you
-  # want to log everything, set the level to "debug".
-  config.log_level = ENV.fetch('RAILS_LOG_LEVEL', 'info').to_sym
+  # Log to STDOUT by default
+  config.logger = ActiveSupport::Logger.new($stdout)
+                                       .tap  { |logger| logger.formatter = ::Logger::Formatter.new }
+                                       .then { |logger| ActiveSupport::TaggedLogging.new(logger) }
 
   # Prepend all log lines with the following tags.
   config.log_tags = [:request_id]
 
+  # "info" includes generic and useful information about system operation, but avoids logging too much
+  # information to avoid inadvertent exposure of personally identifiable information (PII). If you
+  # want to log everything, set the level to "debug".
+  config.log_level = ENV.fetch('RAILS_LOG_LEVEL', 'info')
+
   # Use a different cache store in production.
   config.cache_store = :redis_cache_store, REDIS_CACHE_PARAMS
 
   # Use a real queuing backend for Active Job (and separate queues per environment).
-  # config.active_job.queue_adapter     = :resque
+  # config.active_job.queue_adapter = :resque
   # config.active_job.queue_name_prefix = "mastodon_production"
 
   config.action_mailer.perform_caching = false
@@ -70,9 +76,8 @@ Rails.application.configure do
   # config.action_mailer.raise_delivery_errors = false
 
   # Enable locale fallbacks for I18n (makes lookups for any locale fall back to
-  # English when a translation cannot be found).
-  # This setting would typically be `true` to use the `I18n.default_locale`.
-  # Some locales are missing translation entries and would have errors:
+  # the I18n.default_locale when a translation cannot be found).
+  # Default value is `true`, but some locales have missing data and would have errors
   # https://github.com/mastodon/mastodon/pull/24727
   config.i18n.fallbacks = [:en]
 
@@ -89,18 +94,8 @@ Rails.application.configure do
     { key: controller.signature_key_id } if controller.respond_to?(:signed_request?) && controller.signed_request?
   end
 
-  # Use a different logger for distributed setups.
-  # require "syslog/logger"
-  # config.logger = ActiveSupport::TaggedLogging.new(Syslog::Logger.new "app-name")
-
-  # Log to STDOUT by default
-  config.logger = ActiveSupport::Logger.new($stdout)
-                                       .tap  { |logger| logger.formatter = ::Logger::Formatter.new }
-                                       .then { |logger| ActiveSupport::TaggedLogging.new(logger) }
-
   # Do not dump schema after migrations.
   config.active_record.dump_schema_after_migration = false
-
   config.action_mailer.perform_caching = false
 
   # E-mails
diff --git a/config/environments/test.rb b/config/environments/test.rb
index 716bf8d31f1..173d09fc405 100644
--- a/config/environments/test.rb
+++ b/config/environments/test.rb
@@ -19,14 +19,15 @@ Rails.application.configure do
   # loading is working properly before deploying your code.
   config.eager_load = ENV['CI'].present?
 
-  config.assets_digest = false
+  # Configure public file server for tests with Cache-Control for performance.
+  config.public_file_server.headers = { 'Cache-Control' => "public, max-age=#{1.hour.to_i}" }
 
   # Show full error reports and disable caching.
-  config.consider_all_requests_local       = true
+  config.consider_all_requests_local = true
   config.action_controller.perform_caching = false
-  config.cache_store = :memory_store
+  config.cache_store = :null_store
 
-  # Raise exceptions instead of rendering exception templates.
+  # Render exception templates for rescuable exceptions and raise for other exceptions.
   config.action_dispatch.show_exceptions = :rescuable
 
   # Disable request forgery protection in test environment.
@@ -34,13 +35,15 @@ Rails.application.configure do
 
   config.action_mailer.perform_caching = false
 
-  config.action_mailer.default_options = { from: 'notifications@localhost' }
-
   # Tell Action Mailer not to deliver emails to the real world.
   # The :test delivery method accumulates sent emails in the
   # ActionMailer::Base.deliveries array.
   config.action_mailer.delivery_method = :test
 
+  # Unlike controllers, the mailer instance doesn't have any context about the
+  # incoming request so you'll need to provide the :host parameter yourself.
+  config.action_mailer.default_url_options = { host: 'www.example.com' }
+
   # Print deprecation notices to the stderr.
   config.active_support.deprecation = :stderr
 
@@ -58,7 +61,6 @@ Rails.application.configure do
   # Raise exceptions for disallowed deprecations.
   config.active_support.disallowed_deprecation = :raise
 
-  config.i18n.default_locale = :en
   config.i18n.fallbacks = true
 
   # Tell Active Support which deprecation messages to disallow.
@@ -70,7 +72,7 @@ Rails.application.configure do
   # Annotate rendered view with file names.
   # config.action_view.annotate_rendered_view_with_filenames = true
 
-  # Raise error when a before_action's only/except options reference missing actions
+  # Raise error when a before_action's only/except options reference missing actions.
   config.action_controller.raise_on_missing_callback_actions = true
 end