diff --git a/app/models/dmsf_file.rb b/app/models/dmsf_file.rb
index fc0dbea4..b433a98b 100644
--- a/app/models/dmsf_file.rb
+++ b/app/models/dmsf_file.rb
@@ -362,7 +362,7 @@ class DmsfFile < ApplicationRecord
     results = scope.where(find_options).uniq.to_a
     results.delete_if { |x| !DmsfFolder.permissions?(x.dmsf_folder) }
 
-    if !options[:titles_only] && RedmineDmsf::Plugin.xapian_available?
+    if !options[:titles_only] && RedmineDmsf::Plugin.lib_available?('xapian')
       database = nil
       begin
         lang = RedmineDmsf.dmsf_stemming_lang
diff --git a/app/views/settings/_dmsf_settings.html.erb b/app/views/settings/_dmsf_settings.html.erb
index 3f1a9343..5c93b670 100644
--- a/app/views/settings/_dmsf_settings.html.erb
+++ b/app/views/settings/_dmsf_settings.html.erb
@@ -355,15 +355,7 @@
     </em>
   </p>
 <% else %>
-  <% begin %>
-    <% require 'xapian' %>
-    <% xapian_disabled = false %>
-  <% rescue LoadError => e %>
-    <p class="warning"><%= l(:warning_xapian_not_available) %></p>
-    <% Rails.logger.warn e.message %>
-    <% xapian_disabled = true %>
-  <% end %>
-  <% if RedmineDmsf::Plugin.xapian_available? %>
+  <% if RedmineDmsf::Plugin.lib_available?('xapian') %>
     <p>
       <%= content_tag :label, l(:label_index_database) %>
       <%= text_field_tag 'settings[dmsf_index_database]', RedmineDmsf.dmsf_index_database, size: 50 %>
diff --git a/lib/redmine_dmsf.rb b/lib/redmine_dmsf.rb
index 4539dd40..3e4d49b5 100644
--- a/lib/redmine_dmsf.rb
+++ b/lib/redmine_dmsf.rb
@@ -253,6 +253,7 @@ unless defined?(EasyPatchManager)
   require "#{File.dirname(__FILE__)}/../patches/access_control_patch"
   require "#{File.dirname(__FILE__)}/../patches/search_patch"
   require "#{File.dirname(__FILE__)}/../patches/custom_field_patch"
+  require "#{File.dirname(__FILE__)}/../patches/puma_patch"
   # A workaround for obsolete 'alias_method' usage in RedmineUp's plugins
   if RedmineDmsf::Plugin.an_obsolete_plugin_present?
     require "#{File.dirname(__FILE__)}/../patches/notifiable_ru_patch"
diff --git a/lib/redmine_dmsf/plugin.rb b/lib/redmine_dmsf/plugin.rb
index 15775386..e4dcbbdc 100644
--- a/lib/redmine_dmsf/plugin.rb
+++ b/lib/redmine_dmsf/plugin.rb
@@ -39,12 +39,12 @@ module RedmineDmsf
       false
     end
 
-    # Return true if Xapian binding is installed (gem ruby_xapian)
-    def self.xapian_available?
-      require 'xapian'
+    # Return true if the given gem is installed
+    def self.lib_available?(path)
+      require path
       true
     rescue LoadError => e
-      Rails.logger.warn e.message
+      Rails.logger.info e.message
       false
     end
   end
diff --git a/patches/puma_patch.rb b/patches/puma_patch.rb
new file mode 100644
index 00000000..37eaeecb
--- /dev/null
+++ b/patches/puma_patch.rb
@@ -0,0 +1,45 @@
+# frozen_string_literal: true
+
+# Redmine plugin for Document Management System "Features"
+#
+# Karel Pičman <karel.picman@kontron.com>
+#
+# This program is free software; you can redistribute it and/or
+# modify it under the terms of the GNU General Public License
+# as published by the Free Software Foundation; either version 2
+# of the License, or (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program; if not, write to the Free Software
+# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
+#
+# Redmine's PDF export patch to view DMS images
+
+module RedmineDmsf
+  module Patches
+    # Puma
+    module PumaPatch
+      ##################################################################################################################
+      # Overridden methods
+      def self.included(base)
+        base.class_eval do
+          # WebDAV methods
+          methods = Puma::Const::SUPPORTED_HTTP_METHODS |
+                    %w[OPTIONS HEAD GET PUT POST DELETE PROPFIND PROPPATCH MKCOL COPY MOVE LOCK UNLOCK]
+          remove_const :SUPPORTED_HTTP_METHODS
+          const_set :SUPPORTED_HTTP_METHODS, methods.freeze
+        end
+      end
+    end
+  end
+end
+
+# Apply the patch
+if !defined?(EasyPatchManager) && RedmineDmsf::Plugin.lib_available?('puma/const')
+  Puma::Const.include RedmineDmsf::Patches::PumaPatch
+end
diff --git a/test/unit/lib/redmine_dmsf/dmsf_plugin_test.rb b/test/unit/lib/redmine_dmsf/dmsf_plugin_test.rb
index c34ac8c5..a3ded3e9 100644
--- a/test/unit/lib/redmine_dmsf/dmsf_plugin_test.rb
+++ b/test/unit/lib/redmine_dmsf/dmsf_plugin_test.rb
@@ -42,4 +42,9 @@ class DmsfPluginTest < RedmineDmsf::Test::HelperTest
     assert RedmineDmsf::Plugin.an_obsolete_plugin_present?
     FileUtils.rm_rf path
   end
+
+  def test_lib_available?
+    assert RedmineDmsf::Plugin.lib_available?('zip')
+    assert_not RedmineDmsf::Plugin.lib_available?('not_existing_gem')
+  end
 end