diff --git a/forms/source/component/Grid.hxx b/forms/source/component/Grid.hxx
index 02cfef64ffb1..0d6270508098 100644
--- a/forms/source/component/Grid.hxx
+++ b/forms/source/component/Grid.hxx
@@ -36,8 +36,6 @@
 namespace frm
 {
 
-class OGridColumn;
-
 // OGridControlModel
 
 typedef ::cppu::ImplHelper7 <   css::awt::XControlModel
diff --git a/forms/source/component/GroupManager.hxx b/forms/source/component/GroupManager.hxx
index 4cefd7ac3a12..18f2d8a25df9 100644
--- a/forms/source/component/GroupManager.hxx
+++ b/forms/source/component/GroupManager.hxx
@@ -104,7 +104,6 @@ public:
 };
 
 
-class OGroupComp;
 class OGroupCompAcc
 {
     css::uno::Reference< css::beans::XPropertySet>    m_xComponent;
diff --git a/forms/source/inc/controlfeatureinterception.hxx b/forms/source/inc/controlfeatureinterception.hxx
index 8603a4594e2d..9b1905bba52f 100644
--- a/forms/source/inc/controlfeatureinterception.hxx
+++ b/forms/source/inc/controlfeatureinterception.hxx
@@ -31,8 +31,6 @@ namespace frm
 {
 
 
-    class UrlTransformer;
-
     //= ControlFeatureInterception
 
     /** helper class for controls which allow some of their features to be intercepted
diff --git a/forms/source/richtext/richtextimplcontrol.hxx b/forms/source/richtext/richtextimplcontrol.hxx
index 86b1a1831684..c227fc62ac9f 100644
--- a/forms/source/richtext/richtextimplcontrol.hxx
+++ b/forms/source/richtext/richtextimplcontrol.hxx
@@ -27,7 +27,6 @@
 #include <map>
 
 class EditView;
-class EditStatus;
 namespace vcl { class Window; }
 class SvxScriptSetItem;
 
@@ -37,7 +36,6 @@ namespace frm
 
     class ITextAttributeListener;
     class ITextSelectionListener;
-    class RichTextViewPort;
 
     class RichTextControlImpl : public IEngineStatusListener
     {
diff --git a/forms/source/richtext/richtextmodel.hxx b/forms/source/richtext/richtextmodel.hxx
index cf0bae7db435..23c4b67101ed 100644
--- a/forms/source/richtext/richtextmodel.hxx
+++ b/forms/source/richtext/richtextmodel.hxx
@@ -30,8 +30,6 @@
 #include <tools/link.hxx>
 #include <memory>
 
-class EditEngine;
-
 namespace frm
 {
 
diff --git a/forms/source/richtext/textattributelistener.hxx b/forms/source/richtext/textattributelistener.hxx
index 3025d7b5d626..80dbb6bd21d5 100644
--- a/forms/source/richtext/textattributelistener.hxx
+++ b/forms/source/richtext/textattributelistener.hxx
@@ -20,8 +20,6 @@
 
 #include "rtattributes.hxx"
 
-struct ESelection;
-
 namespace frm
 {
 
diff --git a/forms/source/solar/inc/navtoolbar.hxx b/forms/source/solar/inc/navtoolbar.hxx
index 18e0e806df34..c8c34114a41c 100644
--- a/forms/source/solar/inc/navtoolbar.hxx
+++ b/forms/source/solar/inc/navtoolbar.hxx
@@ -26,7 +26,6 @@ namespace frm
 {
     class IFeatureDispatcher;
     class DocumentCommandImageProvider;
-    class ICommandDescriptionProvider;
     class ImplNavToolBar;
     typedef std::shared_ptr< const DocumentCommandImageProvider >  PCommandImageProvider;
 
diff --git a/forms/source/xforms/binding.hxx b/forms/source/xforms/binding.hxx
index 70cf81e4468d..538d5a401ee9 100644
--- a/forms/source/xforms/binding.hxx
+++ b/forms/source/xforms/binding.hxx
@@ -46,7 +46,6 @@ namespace xforms
 }
 namespace com::sun::star {
     namespace xml {
-        namespace xpath { class XXPathAPI; }
         namespace dom
         {
             class XNode;
diff --git a/forms/source/xforms/computedexpression.hxx b/forms/source/xforms/computedexpression.hxx
index 0f650b50583a..d61cc97bbcdb 100644
--- a/forms/source/xforms/computedexpression.hxx
+++ b/forms/source/xforms/computedexpression.hxx
@@ -27,12 +27,9 @@ namespace com::sun::star
 {
     namespace xml
     {
-        namespace dom { class XNode; }
-        namespace dom { class XNodeset; }
         namespace xpath { class XXPathAPI; }
         namespace xpath { class XXPathObject; }
     }
-    namespace container { class XNameContainer; }
 }
 namespace xforms { class EvaluationContext; }
 
diff --git a/forms/source/xforms/convert.hxx b/forms/source/xforms/convert.hxx
index c7073f7c36cd..e5e2cd9738ab 100644
--- a/forms/source/xforms/convert.hxx
+++ b/forms/source/xforms/convert.hxx
@@ -25,7 +25,6 @@
 namespace com::sun::star::uno
 {
     class Any;
-    class Type;
 }
 
 namespace xforms
diff --git a/forms/source/xforms/datatypes.hxx b/forms/source/xforms/datatypes.hxx
index db1500402a9d..bc1428ab7bab 100644
--- a/forms/source/xforms/datatypes.hxx
+++ b/forms/source/xforms/datatypes.hxx
@@ -367,7 +367,6 @@ namespace xforms
 
 
 
-    class ODateTimeType;
     typedef ODerivedDataType< OTimeType, OValueLimitedType< css::util::DateTime > > ODateTimeType_Base;
     class ODateTimeType : public ODateTimeType_Base
     {
diff --git a/forms/source/xforms/enumeration.hxx b/forms/source/xforms/enumeration.hxx
index 6374e0c8ef27..913602c8dc7f 100644
--- a/forms/source/xforms/enumeration.hxx
+++ b/forms/source/xforms/enumeration.hxx
@@ -26,10 +26,6 @@
 
 namespace com::sun::star {
     namespace container { class XIndexAccess; }
-    namespace uno { class Any; }
-    namespace container { class NoSuchElementException; }
-    namespace lang { class WrappedTargetException; }
-    namespace uno { class RuntimeException; }
 }
 
 /** implement XEnumeration based on container::XIndexAccess */
diff --git a/forms/source/xforms/model.hxx b/forms/source/xforms/model.hxx
index 94d3f3e052fe..bd0a85acd578 100644
--- a/forms/source/xforms/model.hxx
+++ b/forms/source/xforms/model.hxx
@@ -36,13 +36,8 @@ namespace com::sun::star
 {
     namespace xml::dom { class XDocument; }
     namespace xml::dom { class XNode; }
-    namespace uno { template<typename T> class Sequence; }
-    namespace lang { class IndexOutOfBoundsException; }
-    namespace lang { class IllegalArgumentException; }
     namespace beans { class XPropertySet; }
-    namespace container { class XSet; }
     namespace container { class XNameContainer; }
-    namespace frame { class XModel; }
 }
 namespace xforms
 {
diff --git a/forms/source/xforms/pathexpression.hxx b/forms/source/xforms/pathexpression.hxx
index b26325b9cddf..233062a9bbca 100644
--- a/forms/source/xforms/pathexpression.hxx
+++ b/forms/source/xforms/pathexpression.hxx
@@ -26,11 +26,11 @@
 // forward declarations
 namespace com::sun::star::xml::dom
 {
-class XNodeList;
-namespace events
-{
-class XEventListener;
+class XNode;
 }
+namespace com::sun::star::xml::dom
+{
+class XNodeList;
 }
 
 namespace xforms
diff --git a/forms/source/xforms/propertysetbase.hxx b/forms/source/xforms/propertysetbase.hxx
index d6ae97405880..d2d627b9ad28 100644
--- a/forms/source/xforms/propertysetbase.hxx
+++ b/forms/source/xforms/propertysetbase.hxx
@@ -28,12 +28,6 @@
 #include <map>
 #include <memory>
 
-namespace com::sun::star::uno {
-        class Any;
-        class RuntimeException;
-        template<class T> class Sequence;
-}
-
 /** base class which encapsulates accessing (reading/writing) concrete property values
 */
 class PropertyAccessorBase : public salhelper::SimpleReferenceObject
diff --git a/forms/source/xforms/submission.hxx b/forms/source/xforms/submission.hxx
index cf6ec8402720..70b4a8eca265 100644
--- a/forms/source/xforms/submission.hxx
+++ b/forms/source/xforms/submission.hxx
@@ -33,11 +33,6 @@
 // forward declarations
 namespace com::sun::star {
     namespace xforms { class XModel; }
-    namespace uno { class Any; }
-    namespace beans { class UnknownPropertyException;
-                      class PropertyVetoException; }
-    namespace lang { class IllegalArgumentException;
-                     class WrappedTargetException; }
 }
 namespace xforms { class Model; }
 
diff --git a/forms/source/xforms/submission/submission.hxx b/forms/source/xforms/submission/submission.hxx
index 26a2514c829d..160744fc37e7 100644
--- a/forms/source/xforms/submission/submission.hxx
+++ b/forms/source/xforms/submission/submission.hxx
@@ -41,10 +41,6 @@
 #include <mutex>
 #include <utility>
 
-class CSubmissionPut;
-class CSubmissionPost;
-class CSubmissionGet;
-
 class CCommandEnvironmentHelper final : public cppu::WeakImplHelper< css::ucb::XCommandEnvironment >
 {
     friend class CSubmissionPut;
diff --git a/forms/source/xforms/unohelper.hxx b/forms/source/xforms/unohelper.hxx
index 5aace2f3cf65..7d4d2972184a 100644
--- a/forms/source/xforms/unohelper.hxx
+++ b/forms/source/xforms/unohelper.hxx
@@ -22,7 +22,6 @@
 
 namespace com::sun::star {
     namespace uno {
-        class XInterface;
         template<class T> class Reference;
     }
     namespace beans {