In our Condfluence DC app the Actions stoped working

After upgrading to Confluence 10 our team tried to do every necessary modification in our custom app to make compatible with the new version. But we cannot get the Actions working.
We changed the xwork tags to struts tags in our atlassian-plugin.xml, but we cannot find anything in the documentations that we need to do more. Now we get this error when we try to do an Action:
java.lang.IllegalStateException: Error loading action class
...
Caused by: java.lang.ClassNotFoundException: com.catworkx.confluence.dme.actions.ClearBrokenAttachmentsAction
Here is our atlassian-plugin.xml:

<atlassian-plugin key="${atlassian.plugin.key}" name="${project.name}" plugins-version="2">

    <plugin-info>

        <description>${project.description}</description>

        <version>${project.version}</version>

        <vendor name="${project.organization.name}" url="${project.organization.url}" />

        <param name="plugin-icon">images/plugin-icon.png</param>

        <param name="plugin-logo">images/plugin-logo.png</param>

        <param name="vendor-icon">images/vendor-icon.png</param>

        <param name="vendor-logo">images/vendor-logo.png</param>

        <param name="configure.url">/plugins/servlet/cwx-dme/settings</param>

        <param name="atlassian-data-center-compatible">true</param>

    </plugin-info>



    <resource type="i18n" name="i18n" location="translations.document-management-extensions"/>



    <web-resource key="cwx-dme-copy-dialog-resources-${project.version}" name="Copy Dialog Web Resources">

        <resource type="download" name="cwx-dme-copy-dialog.js" location="/js/cwx-dme-copy-dialog.js" />

        <resource type="download" name="cwx-dme-copy-dialog.css" location="/css/cwx-dme-copy-dialog.css" />

        <resource type="download" name="cwx-dme-copy-template-metadata-dialog.js" location="/js/cwx-dme-copy-template-metadata-dialog.js" />

        <resource type="download" name="cwx-dme-propagate-metadata-dialog.js" location="/js/cwx-dme-propagate-metadata-dialog.js" />

        <resource type="download" name="cwx-dme-copy-all-metadata-dialog.js" location="/js/cwx-dme-copy-all-metadata-dialog.js" />

        <dependency>com.atlassian.auiplugin:ajs</dependency>

        <dependency>com.atlassian.auiplugin:dialog2</dependency>

        <context>page</context>

        <context>cwx-dme-copy-dialog</context>

    </web-resource>

    <web-resource key="cwx-dme-settings-resources-${project.version}" name="Settings Web Resources">

        <resource type="download" name="cwx-dme-settings.js" location="/js/cwx-dme-settings.js" />

        <dependency>com.atlassian.auiplugin:ajs</dependency>

        <dependency>com.atlassian.auiplugin:aui-select2</dependency>

        <context>cwx-dme-settings</context>

    </web-resource>



    <web-resource key="cwx-dme-clear-attachments-resources-${project.version}" name="Settings Web Resources">

        <resource type="download" name="cwx-dme-settings.js" location="/js/cwx-dme-settings.js" />

        <dependency>com.atlassian.auiplugin:ajs</dependency>

        <dependency>com.atlassian.auiplugin:aui-select2</dependency>

        <context>cwx-dme-settings</context>

    </web-resource>



    <component-import key="ao" name="Active Objects" interface="com.atlassian.activeobjects.external.ActiveObjects" />

    <component-import key="templateRenderer" name="Template Renderer" interface="com.atlassian.templaterenderer.TemplateRenderer" />

    <component-import key="i18n" name="I18n Resolver" interface="com.atlassian.sal.api.message.I18nResolver" />

    <component-import key="userManager" name="User Manager" interface="com.atlassian.sal.api.user.UserManager" />

    <component-import key="loginUriProvider" name="Login URI Provider" interface="com.atlassian.sal.api.auth.LoginUriProvider" />

    <component-import key="transactionTemplate" name="Transaction Template" interface="com.atlassian.sal.api.transaction.TransactionTemplate" />

    <component-import key="applicationProperties" name="Application Properties" interface="com.atlassian.sal.api.ApplicationProperties" />

    <component-import key="metadataManager" interface="com.communardo.confluence.metadata.service.MetadataManager" />



    <component key="cwxDmeEntityManager" name="Entity Manager" class="com.catworkx.confluence.dme.ao.DmeEntityManagerImpl">

        <interface>com.catworkx.confluence.dme.ao.DmeEntityManager</interface>

    </component>

    <component key="cwxDmeSettingsManager" name="Settings Manager" class="com.catworkx.confluence.dme.settings.SettingsManager" />

    <component key="cwxDmeScrollHelper" name="Scroll Helper" class="com.catworkx.confluence.dme.utils.ScrollHelper" />

    <component key="cwxDmeCopyPageService" name="Copy Page Service" class="com.catworkx.confluence.dme.services.CopyPageService" />

    <component key="cwxDmeMetadataCopyService" name="Metadata Copy Service" class="com.catworkx.confluence.dme.services.MetadataCopyService" />

    <component key="cwxDmeClearBrokenAttachments" name="Clear Broken Attachments Service" class="com.catworkx.confluence.dme.services.ClearBrokenAttachmentsService" />

    <ao key="ao-module" name="Active Objects module" namespace="com.catworkx.confluence.document-management-extensions">

        <entity>com.catworkx.confluence.dme.ao.SettingsEntry</entity>

    </ao>



    <rest name="Document Management Extensions Rest Resource" key="cwx-dme-rest-resource" path="/cwx-dme" version="1.0" />



    <web-item key="cwx-dme-copy-page-tree-web-item" name="Copy Page Tree Web Item" section="system.content.action/modify" weight="12">

        <label key="cwx.dme.copy-page-tree" />

        <link linkId="cwx-dme-copy-page-tree-link">/pages/cwx-dme-copy-page-tree.action?idOfPageToCopy=$helper.page.id&amp;spaceKey=$helper.space.key</link>

        <condition class="com.atlassian.confluence.plugin.descriptor.web.conditions.HasPageCondition" />

        <condition class="com.atlassian.confluence.plugin.descriptor.web.conditions.CreatePageOrBlogpostCondition">

            <param name="contentType">page</param>

        </condition>

        <condition class="com.catworkx.confluence.dme.web.conditions.IsAllowedSpaceCondition" />

        <styleClass>action-copy</styleClass>

    </web-item>

    <struts key="cwx-dme-copy-page-tree-action" name="Copy Page Tree Action">

        <package name="cwx-dme-copy-page-tree" extends="default" namespace="/pages">

            <default-interceptor-ref name="defaultStack" />

            <action name="cwx-dme-copy-page-tree" class="com.catworkx.confluence.dme.actions.CopyPageTreeDialog">

                <result name="success" type="velocity">/templates/cwx-dme-copy-page-tree.vm</result>

            </action>

        </package>

    </struts>



    <web-item key="cwx-dme-copy-template-web-item" name="Copy Template Web Item" section="system.content.action/modify" weight="13">

        <label key="cwx.dme.copy-template" />

        <link linkId="cwx-dme-copy-template-link">/pages/cwx-dme-copy-template.action?idOfPageToCopy=$helper.page.id&amp;spaceKey=$helper.space.key</link>

        <condition class="com.atlassian.confluence.plugin.descriptor.web.conditions.HasPageCondition" />

        <condition class="com.atlassian.confluence.plugin.descriptor.web.conditions.CreatePageOrBlogpostCondition">

            <param name="contentType">page</param>

        </condition>

        <condition class="com.catworkx.confluence.dme.web.conditions.IsAllowedSpaceCondition" />

        <styleClass>action-copy</styleClass>

    </web-item>

    <struts key="cwx-dme-copy-template-action" name="Copy Template Action">

        <package name="cwx-dme-copy-template" extends="default" namespace="/pages">

            <default-interceptor-ref name="defaultStack" />

            <action name="cwx-dme-copy-template" class="com.catworkx.confluence.dme.actions.CopyTemplateDialog">

                <result name="success" type="velocity">/templates/cwx-dme-copy-template.vm</result>

            </action>

        </package>

    </struts>



    <web-item key="cwx-dme-copy-template-metadata-web-item" name="Copy Template Metadata Web Item" section="system.content.action/modify" weight="14">

        <label key="cwx.dme.copy-template-metadata" />

        <link linkId="cwx-dme-copy-template-metadata-link">/pages/cwx-dme-copy-template-metadata.action?pageId=$helper.page.id</link>

        <condition class="com.atlassian.confluence.plugin.descriptor.web.conditions.PagePermissionCondition">

            <param name="permission">edit</param>

        </condition>

        <condition class="com.catworkx.confluence.dme.web.conditions.IsAllowedSpaceCondition" />

        <styleClass>action-copy</styleClass>

    </web-item>

    <struts key="cwx-dme-copy-template-metadata-action" name="Copy Template Metadata Action">

        <package name="cwx-dme-copy-template-metadata" extends="default" namespace="/pages">

            <default-interceptor-ref name="defaultStack" />

            <action name="cwx-dme-copy-template-metadata" class="com.catworkx.confluence.dme.actions.CopyTemplateMetadataDialog">

                <result name="success" type="velocity">/templates/cwx-dme-copy-template-metadata.vm</result>

            </action>

        </package>

    </struts>



    <web-item key="cwx-dme-propagate-metadata-web-item" name="Propagate Metadata Web Item" section="system.content.action/modify" weight="15">

        <label key="cwx.dme.propagate-metadata" />

        <link linkId="cwx-dme-propagate-metadata-link">/pages/cwx-dme-propagate-metadata.action?pageId=$helper.page.id</link>

        <condition class="com.atlassian.confluence.plugin.descriptor.web.conditions.SpacePermissionCondition">

            <param name="permission">edit</param>

        </condition>

        <condition class="com.catworkx.confluence.dme.web.conditions.CanPropagateMetadataCondition" />

        <condition class="com.catworkx.confluence.dme.web.conditions.IsAllowedSpaceCondition" />

        <styleClass>action-copy</styleClass>

    </web-item>



    <struts key="cwx-dme-propagate-metadata-action" name="Propagate Metadata Action">

        <package name="cwx-dme-propagate-metadata" extends="default" namespace="/pages">

            <default-interceptor-ref name="defaultStack" />

            <action name="cwx-dme-propagate-metadata" class="com.catworkx.confluence.dme.actions.PropagateMetadataDialog">

                <result name="success" type="velocity">/templates/cwx-dme-propagate-metadata.vm</result>

            </action>

        </package>

    </struts>



    <web-item key="cwx-dme-copy-all-communardo-metadata-web-item" name="Copy All Communardo Metadata Web Item" section="system.content.action/modify" weight="16">

        <label key="cwx.dme.copy-all-metadata" />

        <link linkId="cwx-dme-copy-all-communardo-metadata-link">/cwx-dme-copy-all-metadata.action?pageId=$helper.page.id</link>

        <condition class="com.atlassian.confluence.plugin.descriptor.web.conditions.PagePermissionCondition">

            <param name="permission">edit</param>

        </condition>

        <condition class="com.catworkx.confluence.dme.web.conditions.IsAllowedSpaceForCopyAllMetadataCondition" />

        <styleClass>action-copy</styleClass>

    </web-item>

    <struts key="cwx-dme-copy-all-metadata-action" name="Copy All Metadata Action">

        <package name="cwx-dme-copy-all-metadata" extends="default" namespace="/">

            <default-interceptor-ref name="defaultStack" />

            <action name="cwx-dme-copy-all-metadata" class="com.catworkx.confluence.dme.actions.CopyAllMetadataDialog">

                <result name="success" type="velocity">/templates/cwx-dme-copy-all-metadata.vm</result>

            </action>

        </package>

    </struts>



    <web-resource key="cwx-dme-clear-broken-attachments-${project.version}" name="Clear Broken Attachments Resources">

        <resource type="download" name="cwx-dme-clear-broken-attachments.js" location="/js/cwx-dme-clear-broken-attachments.js" />

        <dependency>com.atlassian.auiplugin:ajs</dependency>

        <context>space</context>

    </web-resource>

    <web-item key="cwx-dme-clear-broken-attachment" name="Clear Broken Attachments" section="system.space.tools/contenttools" weight="100">

      <label key="cwx.dme.clear-broken-attachments" />

      <link linkId="space-admin-clear-broken-attachment-id">/cwx-dme-clear-broken-attachments.action?spaceKey=$generalUtil.urlEncode($helper.spaceKey)</link>

      <condition class="com.atlassian.confluence.plugin.descriptor.web.conditions.SpaceSidebarCondition"/>

    </web-item>

    <struts key="cwx-dme-clear-broken-attachment-action" name="Clear Broken Attachments Action">

        <package name="cwx-dme-clear-broken-attachments" extends="default" namespace="/">

            <default-interceptor-ref name="defaultStack" />

            <action name="cwx-dme-clear-broken-attachments" class="com.catworkx.confluence.dme.actions.ClearBrokenAttachmentsAction">

                <result name="success" type="velocity">/templates/cwx-dme-clear-broken-attachments.vm</result>

            </action>

        </package>

    </struts>



    <web-section key="cwx-dme-admin-section" name="Document Management Extensions Admin Section" location="system.admin" weight="500">

        <label key="cwx.dme.admin.section.name" />

        <condition class="com.atlassian.confluence.plugin.descriptor.web.conditions.ConfluenceAdministratorCondition" />

    </web-section>

    <web-item key="cwx-dme-settings-item" name="Document Management Extensions Settings Item" section="system.admin/cwx-dme-admin-section" weight="1">

        <label key="cwx.dme.settings.item.name" />

        <link linkId="cwx-dme-settings-item-link">/plugins/servlet/cwx-dme/settings</link>

    </web-item>

    <servlet name="Settings Servlet" key="cwx-dme-settings-servlet" class="com.catworkx.confluence.dme.servlets.SettingsServlet">

        <url-pattern>/cwx-dme/settings</url-pattern>

    </servlet>



    <web-item key="cwx-dme-delegated-admin-settings-item" name="Document Management Extensions Delegated Admin Settings Item" section="system.header/spaces-menu" weight="50">

        <label key="cwx.dme.delegated-admin-settings.item.name" />

        <link linkId="cwx-dme-delegated-admin-settings-item-link">/plugins/servlet/cwx-dme/delegated-admin-settings</link>

        <condition class="com.catworkx.confluence.dme.web.conditions.IsDelegatedAdminCondition" />

    </web-item>

    <servlet name="Delegated Admin Settings Servlet" key="cwx-dme-delegated-admin-settings-servlet" class="com.catworkx.confluence.dme.servlets.DelegatedAdminSettingsServlet">

        <url-pattern>/cwx-dme/delegated-admin-settings</url-pattern>

    </servlet>



    <xhtml-macro key="cwx-dme-button-macro" name="cwx-dme-button-macro" class="com.catworkx.confluence.dme.macros.DocumentManagementButtonMacro">

        <category name="navigation" />

        <device-type>mobile</device-type>

        <parameters>

            <parameter name="action" type="enum" required="true">

                <value name="copy-template" />

                <value name="copy-page-tree" />

                <value name="propagate-metadata" />

                <value name="copy-template-metadata" />

            </parameter>

            <parameter name="label" type="string" />

        </parameters>

    </xhtml-macro>



</atlassian-plugin>


Here is the action class:

package com.catworkx.confluence.dme.actions;



import org.apache.struts2.interceptor.parameter.StrutsParameter;

import org.slf4j.Logger;

import org.slf4j.LoggerFactory;



import com.atlassian.confluence.spaces.actions.AbstractSpaceAction;

import com.atlassian.confluence.spaces.actions.SpaceAware;



public class ClearBrokenAttachmentsAction extends AbstractSpaceAction implements SpaceAware { // NOSONAR



  private final static Logger LOG = LoggerFactory.getLogger(ClearBrokenAttachmentsAction.class);



  private static final long serialVersionUID = 7262680848675633155L;



  private String spaceKey;



  public ClearBrokenAttachmentsAction() {

    super();

    ClearBrokenAttachmentsAction.LOG.error("Constructor is called");

  }



  @Override

  public String getSpaceKey() {

    return this.spaceKey;

  }



  @Override

  public boolean isSpaceRequired() {

    return true;

  }



  @Override

  public boolean isViewPermissionRequired() {

    return true;

  }



  @StrutsParameter

  public void setSpaceKey(final String spaceKey) {

    this.spaceKey = spaceKey;

  }



}


Could you please, advise here what do we have to modify to make the actions work again? Thank you in advance.
Best regards,
Valeria