diff --git a/Gemfile b/Gemfile
index 9329f3ab0..ea47e9ad7 100644
--- a/Gemfile
+++ b/Gemfile
@@ -136,7 +136,7 @@ group :development do
   gem 'binding_of_caller', '~> 0.7'
   gem 'bullet', '~> 6.1'
   gem 'letter_opener', '~> 1.7'
-  gem 'letter_opener_web', '~> 1.3'
+  gem 'letter_opener_web', '~> 1.4'
   gem 'memory_profiler'
   gem 'rubocop', '~> 0.79', require: false
   gem 'rubocop-rails', '~> 2.4', require: false
diff --git a/Gemfile.lock b/Gemfile.lock
index c8a37dd4b..607813f84 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -333,7 +333,7 @@ GEM
       addressable (~> 2.3)
     letter_opener (1.7.0)
       launchy (~> 2.2)
-    letter_opener_web (1.3.4)
+    letter_opener_web (1.4.0)
       actionmailer (>= 3.2)
       letter_opener (~> 1.0)
       railties (>= 3.2)
@@ -717,7 +717,7 @@ DEPENDENCIES
   json-ld-preloaded (~> 3.0)
   kaminari (~> 1.1)
   letter_opener (~> 1.7)
-  letter_opener_web (~> 1.3)
+  letter_opener_web (~> 1.4)
   link_header (~> 0.0)
   lograge (~> 0.11)
   makara (~> 0.4)