kind of works with importmaps

app/assets/config/manifest.js

@@ -1,5 +0,0 @@
-//= link_tree ../images
-//= link_directory ../stylesheets .css
-//= link_tree ../../javascript .js
-//= link_tree ../javascripts .js
-//= link_tree ../../../vendor/javascript .js

app/views/layouts/_header.html.haml

@@ -20,12 +20,11 @@
       \==================================================
     / Placed at the end of the document so the pages load faster
     = javascript_importmap_tags
+    = javascript_include_tag "application_legacy"
 
-    -# = javascript_include_tag "application"
-
-    -# :javascript
-    -#   I18n.defaultLocale = "#{I18n.default_locale}";
-    -#   I18n.locale = "#{I18n.locale}";
-    -#   I18n.fallbacks = true;
-    -# = yield(:javascript)
+    :javascript
+      I18n.defaultLocale = "#{I18n.default_locale}";
+      I18n.locale = "#{I18n.locale}";
+      I18n.fallbacks = true;
+    = yield(:javascript)
     = raw FoodsoftConfig[:webstats_tracking_code]

config/importmap.rb

@@ -1,3 +1,2 @@
 # Pin npm packages by running ./bin/importmap
-
-pin "application", preload: true
+pin "application", preload: true

config/initializers/assets.rb

@@ -9,4 +9,4 @@ Rails.application.config.assets.version = '1.0'
 # Precompile additional assets.
 # application.js, application.css, and all non-JS/CSS in the app/assets
 # folder are already added.
-Rails.application.config.assets.precompile += %w( jquery.min.js )
+Rails.application.config.assets.precompile += %w( application_legacy.js jquery.min.js )