Merge remote-tracking branch 'upstream/pull/2452'

diff --cc Gemfile
index 983bf9f92464a1628c84c67e3302774c4697716a,d7739491172f55d499e652c2bc6941bde9f62bf8..466d733235ab4b8d59e59837ad2f3e608199dd60
--- 1/Gemfile
--- 2/Gemfile
+++ b/Gemfile
@@@ -40,9 -40,9 +40,10 @@@ gem "autoprefixer-rails
  gem "image_optim_rails"
  
  # Load rails plugins
 +gem "actionpack-page_caching", ">= 1.2.0"
  gem "active_record_union"
  gem "activerecord-import"
+ gem "bootstrap", "~> 4.3.1"
  gem "cancancan"
  gem "composite_primary_keys", "~> 12.0.0"
  gem "config"

diff --cc Gemfile.lock
index 0c1707be319888be12f6d3f94a9a1a0ea7d52bc0,5af33d9a18ed98d05f94725d75e6e6268c58ae80..cc2d7deafde8f9b4e990cc519a6d0c83efa292c2
--- 1/Gemfile.lock
--- 2/Gemfile.lock
+++ b/Gemfile.lock
@@@ -106,8 -104,12 +106,12 @@@ GE
        debug_inspector (>= 0.0.1)
      bootsnap (1.4.5)
        msgpack (~> 1.0)
+     bootstrap (4.3.1)
+       autoprefixer-rails (>= 9.1.0)
+       popper_js (>= 1.14.3, < 2)
+       sassc-rails (>= 2.0.0)
      browser (2.7.1)
 -    builder (3.2.3)
 +    builder (3.2.4)
      bzip2-ffi (1.0.0)
        ffi (~> 1.0)
      cancancan (3.0.1)

diff --cc app/assets/stylesheets/common.scss
Simple merge