diff --git a/src/invidious/routes/preferences.cr b/src/invidious/routes/preferences.cr
index 112535bd..05bc2714 100644
--- a/src/invidious/routes/preferences.cr
+++ b/src/invidious/routes/preferences.cr
@@ -214,7 +214,7 @@ module Invidious::Routes::PreferencesRoute
         statistics_enabled ||= "off"
         CONFIG.statistics_enabled = statistics_enabled == "on"
 
-        CONFIG.modified_source_code_url = env.params.body["modified_source_code_url"]?.try &.as(String)
+        CONFIG.modified_source_code_url = env.params.body["modified_source_code_url"]?.presence
 
         File.write("config/config.yml", CONFIG.to_yaml)
       end
diff --git a/src/invidious/views/user/preferences.ecr b/src/invidious/views/user/preferences.ecr
index 55349c5a..b89c73ca 100644
--- a/src/invidious/views/user/preferences.ecr
+++ b/src/invidious/views/user/preferences.ecr
@@ -310,7 +310,7 @@
 
                 <div class="pure-control-group">
                     <label for="modified_source_code_url"><%= translate(locale, "adminprefs_modified_source_code_url_label") %></label>
-                    <input name="modified_source_code_url" id="modified_source_code_url" type="input" <% if CONFIG.modified_source_code_url %>checked<% end %>>
+                    <input name="modified_source_code_url" id="modified_source_code_url" type="url" value="<%= CONFIG.modified_source_code_url %>">
                 </div>
             <% end %>