After installing the plugin and restarting redmine, an error appears.

        69: from bin/rails:4:in `<main>'
        68: from bin/rails:4:in `require'
        67: from /usr/local/lib/ruby/gems/2.5.0/gems/railties-5.2.4.2/lib/rails/commands.rb:18:in `<top (required)>'
        66: from /usr/local/lib/ruby/gems/2.5.0/gems/railties-5.2.4.2/lib/rails/command.rb:46:in `invoke'
        65: from /usr/local/lib/ruby/gems/2.5.0/gems/railties-5.2.4.2/lib/rails/command/base.rb:69:in `perform'
        64: from /usr/local/lib/ruby/gems/2.5.0/gems/thor-1.2.1/lib/thor.rb:392:in `dispatch'
        63: from /usr/local/lib/ruby/gems/2.5.0/gems/thor-1.2.1/lib/thor/invocation.rb:127:in `invoke_command'
        62: from /usr/local/lib/ruby/gems/2.5.0/gems/thor-1.2.1/lib/thor/command.rb:27:in `run'
        61: from /usr/local/lib/ruby/gems/2.5.0/gems/railties-5.2.4.2/lib/rails/commands/server/server_command.rb:142:in `perform'
        60: from /usr/local/lib/ruby/gems/2.5.0/gems/railties-5.2.4.2/lib/rails/commands/server/server_command.rb:142:in `tap'
        59: from /usr/local/lib/ruby/gems/2.5.0/gems/railties-5.2.4.2/lib/rails/commands/server/server_command.rb:147:in `block in perform'
        58: from /usr/local/lib/ruby/gems/2.5.0/gems/railties-5.2.4.2/lib/rails/commands/server/server_command.rb:53:in `start'
        57: from /usr/local/lib/ruby/gems/2.5.0/gems/rack-2.2.6.2/lib/rack/server.rb:311:in `start'
        56: from /usr/local/lib/ruby/gems/2.5.0/gems/rack-2.2.6.2/lib/rack/server.rb:379:in `handle_profiling'
        55: from /usr/local/lib/ruby/gems/2.5.0/gems/rack-2.2.6.2/lib/rack/server.rb:312:in `block in start'
        54: from /usr/local/lib/ruby/gems/2.5.0/gems/rack-2.2.6.2/lib/rack/server.rb:422:in `wrapped_app'
        53: from /usr/local/lib/ruby/gems/2.5.0/gems/railties-5.2.4.2/lib/rails/commands/server/server_command.rb:27:in `app'
        52: from /usr/local/lib/ruby/gems/2.5.0/gems/rack-2.2.6.2/lib/rack/server.rb:249:in `app'
        51: from /usr/local/lib/ruby/gems/2.5.0/gems/rack-2.2.6.2/lib/rack/server.rb:349:in `build_app_and_options_from_config'
        50: from /usr/local/lib/ruby/gems/2.5.0/gems/rack-2.2.6.2/lib/rack/builder.rb:66:in `parse_file'
        49: from /usr/local/lib/ruby/gems/2.5.0/gems/rack-2.2.6.2/lib/rack/builder.rb:105:in `load_file'
        48: from /usr/local/lib/ruby/gems/2.5.0/gems/rack-2.2.6.2/lib/rack/builder.rb:116:in `new_from_string'
        47: from /usr/local/lib/ruby/gems/2.5.0/gems/rack-2.2.6.2/lib/rack/builder.rb:116:in `eval'
        46: from config.ru:3:in `block in <main>'
        45: from /usr/local/lib/ruby/gems/2.5.0/gems/activesupport-5.2.4.2/lib/active_support/dependencies.rb:291:in `require'
        44: from /usr/local/lib/ruby/gems/2.5.0/gems/activesupport-5.2.4.2/lib/active_support/dependencies.rb:257:in `load_dependency'
        43: from /usr/local/lib/ruby/gems/2.5.0/gems/activesupport-5.2.4.2/lib/active_support/dependencies.rb:291:in `block in require'
        42: from /usr/local/lib/ruby/gems/2.5.0/gems/activesupport-5.2.4.2/lib/active_support/dependencies.rb:291:in `require'
        41: from /opt/redmine-4.0.7/config/environment.rb:15:in `<top (required)>'
        40: from /usr/local/lib/ruby/gems/2.5.0/gems/railties-5.2.4.2/lib/rails/application.rb:361:in `initialize!'
        39: from /usr/local/lib/ruby/gems/2.5.0/gems/railties-5.2.4.2/lib/rails/initializable.rb:60:in `run_initializers'
        38: from /usr/local/lib/ruby/2.5.0/tsort.rb:205:in `tsort_each'
        37: from /usr/local/lib/ruby/2.5.0/tsort.rb:226:in `tsort_each'
        36: from /usr/local/lib/ruby/2.5.0/tsort.rb:347:in `each_strongly_connected_component'
        35: from /usr/local/lib/ruby/2.5.0/tsort.rb:347:in `call'
        34: from /usr/local/lib/ruby/2.5.0/tsort.rb:347:in `each'
        33: from /usr/local/lib/ruby/2.5.0/tsort.rb:349:in `block in each_strongly_connected_component'
        32: from /usr/local/lib/ruby/2.5.0/tsort.rb:431:in `each_strongly_connected_component_from'
        31: from /usr/local/lib/ruby/2.5.0/tsort.rb:350:in `block (2 levels) in each_strongly_connected_component'
        30: from /usr/local/lib/ruby/2.5.0/tsort.rb:228:in `block in tsort_each'
        29: from /usr/local/lib/ruby/gems/2.5.0/gems/railties-5.2.4.2/lib/rails/initializable.rb:61:in `block in run_initializers'
        28: from /usr/local/lib/ruby/gems/2.5.0/gems/railties-5.2.4.2/lib/rails/initializable.rb:32:in `run'
        27: from /usr/local/lib/ruby/gems/2.5.0/gems/railties-5.2.4.2/lib/rails/initializable.rb:32:in `instance_exec'
        26: from /usr/local/lib/ruby/gems/2.5.0/gems/railties-5.2.4.2/lib/rails/application/finisher.rb:69:in `block in <module:Finisher>'
        25: from /usr/local/lib/ruby/gems/2.5.0/gems/railties-5.2.4.2/lib/rails/application/finisher.rb:69:in `each'
        24: from /usr/local/lib/ruby/gems/2.5.0/gems/railties-5.2.4.2/lib/rails/engine.rb:356:in `eager_load!'
        23: from /usr/local/lib/ruby/gems/2.5.0/gems/railties-5.2.4.2/lib/rails/engine.rb:475:in `eager_load!'
        22: from /usr/local/lib/ruby/gems/2.5.0/gems/railties-5.2.4.2/lib/rails/engine.rb:475:in `each'
        21: from /usr/local/lib/ruby/gems/2.5.0/gems/railties-5.2.4.2/lib/rails/engine.rb:477:in `block in eager_load!'
        20: from /usr/local/lib/ruby/gems/2.5.0/gems/railties-5.2.4.2/lib/rails/engine.rb:477:in `each'
        19: from /usr/local/lib/ruby/gems/2.5.0/gems/railties-5.2.4.2/lib/rails/engine.rb:478:in `block (2 levels) in eager_load!'
        18: from /usr/local/lib/ruby/gems/2.5.0/gems/activesupport-5.2.4.2/lib/active_support/dependencies.rb:246:in `require_dependency'
        17: from /usr/local/lib/ruby/gems/2.5.0/gems/activesupport-5.2.4.2/lib/active_support/dependencies.rb:334:in `depend_on'
        16: from /usr/local/lib/ruby/gems/2.5.0/gems/activesupport-5.2.4.2/lib/active_support/dependencies.rb:356:in `require_or_load'
        15: from /usr/local/lib/ruby/gems/2.5.0/gems/activesupport-5.2.4.2/lib/active_support/dependencies.rb:37:in `load_interlock'
        14: from /usr/local/lib/ruby/gems/2.5.0/gems/activesupport-5.2.4.2/lib/active_support/dependencies/interlock.rb:13:in `loading'
        13: from /usr/local/lib/ruby/gems/2.5.0/gems/activesupport-5.2.4.2/lib/active_support/concurrency/share_lock.rb:151:in `exclusive'
        12: from /usr/local/lib/ruby/gems/2.5.0/gems/activesupport-5.2.4.2/lib/active_support/dependencies/interlock.rb:14:in `block in loading'
        11: from /usr/local/lib/ruby/gems/2.5.0/gems/activesupport-5.2.4.2/lib/active_support/dependencies.rb:37:in `block in load_interlock'
        10: from /usr/local/lib/ruby/gems/2.5.0/gems/activesupport-5.2.4.2/lib/active_support/dependencies.rb:378:in `block in require_or_load'
         9: from /usr/local/lib/ruby/gems/2.5.0/gems/activesupport-5.2.4.2/lib/active_support/dependencies.rb:291:in `require'
         8: from /usr/local/lib/ruby/gems/2.5.0/gems/activesupport-5.2.4.2/lib/active_support/dependencies.rb:257:in `load_dependency'
         7: from /usr/local/lib/ruby/gems/2.5.0/gems/activesupport-5.2.4.2/lib/active_support/dependencies.rb:291:in `block in require'
         6: from /usr/local/lib/ruby/gems/2.5.0/gems/activesupport-5.2.4.2/lib/active_support/dependencies.rb:291:in `require'
         5: from /opt/redmine-4.0.7/plugins/redmine_people/lib/redmine_people/patches/attachments_helper_patch.rb:48:in `<top (required)>'
         4: from /opt/redmine-4.0.7/plugins/redmine_people/lib/redmine_people/patches/attachments_helper_patch.rb:48:in `include'
         3: from /opt/redmine-4.0.7/plugins/redmine_people/lib/redmine_people/patches/attachments_helper_patch.rb:28:in `included'
         2: from /opt/redmine-4.0.7/plugins/redmine_people/lib/redmine_people/patches/attachments_helper_patch.rb:28:in `class_eval'
         1: from /opt/redmine-4.0.7/plugins/redmine_people/lib/redmine_people/patches/attachments_helper_patch.rb:31:in `block in included'
/opt/redmine-4.0.7/plugins/redmine_people/lib/redmine_people/patches/attachments_helper_patch.rb:31:in `alias_method': undefined method `container_attachments_download_path' for module `AttachmentsHelper' (NameError)