diff --git a/rails/Dockerfile b/rails/Dockerfile
index 4aebb9b0d..bc2d9a8b2 100644
--- a/rails/Dockerfile
+++ b/rails/Dockerfile
@@ -57,9 +57,7 @@ EXPOSE 3000
 
 ENV RAILS_ENV="production" \
     AUTO_RUN_MIGRATIONS=on \
-    DATABASE_URL="" \
-    OFFLINE_MODE="no" \
-    SECRET_KEY_BASE=""
+    DATABASE_URL=""
 
 RUN apk --no-cache add \
     tzdata \
diff --git a/rails/config/environments/offline.rb b/rails/config/environments/offline.rb
index 1fc940627..69bf38d21 100644
--- a/rails/config/environments/offline.rb
+++ b/rails/config/environments/offline.rb
@@ -31,7 +31,9 @@
   # including the ones that sign and encrypt cookies.
   config.secret_key_base = lambda {
     # Always use configured SECRET_KEY_BASE env var if one is configured
-    if ENV.fetch("SECRET_KEY_BASE", false)
+    # Presence check is to ensure that we don't attempt to set an empty string
+    # as the secret_key_base.
+    if ENV.fetch("SECRET_KEY_BASE", false).present?
       secrets.secret_key_base ||= ENV["SECRET_KEY_BASE"]
     else
       key_file = Rails.root.join("tmp/offline_secret.txt")
@@ -96,8 +98,6 @@
   # Compress CSS using a preproccessor
   # config.assets.css_compressor = :sass
 
-  config.assets.prefix = "/offline-assets"
-
   # Fallback to assets pipeline if a precompiled asset is missed.
   config.assets.compile = false