Fix.

config/initializers/attr_encrypted_no_db_connection.rb

@@ -2,27 +2,19 @@ module AttrEncrypted
   module Adapters
     module ActiveRecord
       def attribute_instance_methods_as_symbols_with_no_db_connection
-        if connection_established?
+        # Use with_connection so the connection doesn't stay pinned to the thread.
+        connected = ::ActiveRecord::Base.connection_pool.with_connection(&:active?) rescue false
+        
+        if connected
           # Call version from AttrEncrypted::Adapters::ActiveRecord
           attribute_instance_methods_as_symbols_without_no_db_connection
         else
-          # Call version from AttrEncrypted (`super` with regards to AttrEncrypted::Adapters::ActiveRecord)
+          # Call version from AttrEncrypted, i.e., `super` with regards to AttrEncrypted::Adapters::ActiveRecord
           AttrEncrypted.instance_method(:attribute_instance_methods_as_symbols).bind(self).call
         end
       end
 
       alias_method_chain :attribute_instance_methods_as_symbols, :no_db_connection
-
-      private
-
-      def connection_established?
-        begin
-          # Use with_connection so the connection doesn't stay pinned to the thread.
-          ActiveRecord::Base.connection_pool.with_connection { |con| con.active? }
-        rescue Exception
-          false
-        end
-      end
     end
   end
 end