Splitter/Menu/ContextMenu: update demo descriptions (#27426)

apps/demos/Demos/ContextMenu/Scrolling/description.md

@@ -1,4 +1,4 @@
-The ContextMenu component supports submenu item scrolling. If the combined item height exceeds the screen size, a scrollbar appears.
+The DevExtreme ContextMenu component supports submenu item scrolling. If combined item height exceeds screen size, a scrollbar appears on-screen.
 
 To restrict submenu height, use the following CSS notation:
 

apps/demos/Demos/Menu/Scrolling/description.md

@@ -1,6 +1,6 @@
-The Menu component supports submenu item scrolling. If the combined item height exceeds the screen size or a pre-defined height limit, a scrollbar appears.
+The DevExtreme Menu component supports submenu item scrolling. If combined item height exceeds screen size or a pre-defined height limit, a scrollbar appears on-screen.
 
-You can use one of the following event handlers to configure submenus:
+You can use one of the following event handlers to configure submenus as requirements dictate:
 
 - [onSubmenuShowing](/Documentation/ApiReference/UI_Components/dxMenu/Configuration/#onSubmenuShowing)
 
@@ -10,6 +10,6 @@ You can use one of the following event handlers to configure submenus:
 
 - [onSubmenuHidden](/Documentation/ApiReference/UI_Components/dxMenu/Configuration/#onSubmenuHidden)
 
-These handlers can access the root submenu element (`submenuContainer`), as well as data from root and submenu items (`itemData`).
+These handlers can access the root submenu element (`submenuContainer`) and data from root and submenu items (`itemData`).
 
-In this demo, the **onSubmenuShowing** function limits the submenu height to 200px.
+In this demo, the **onSubmenuShowing** function limits submenu height to 200px.

apps/demos/Demos/Splitter/Overview/description.md

@@ -1,13 +1,13 @@
-You can use Splitter widgets to create resizable panes on a page.
+You can use our Splitter UI widgets to create resizable panes within your DevExtreme-powered web app/page.
 
 [note] To get started with DevExtreme Splitter, refer to the following tutorial for step-by-step instructions: [Getting Started with Splitter](/Documentation/Guide/UI_Components/Splitter/Getting_Started_with_Splitter/).
 
-To specify splitter panes, set the [items](/Documentation/ApiReference/UI_Components/dxSplitter/Configuration/#items) or [dataSource](/Documentation/ApiReference/UI_Components/dxSplitter/Configuration/#dataSource) property. Use **dataSource** if data is remote or should be processed. If you specify multiple panes, they will appear one after another with splitters between them. 
+To specify individual splitter panes, set the [items](/Documentation/ApiReference/UI_Components/dxSplitter/Configuration/#items) or [dataSource](/Documentation/ApiReference/UI_Components/dxSplitter/Configuration/#dataSource) property. Use **dataSource** if data is remote or should be processed. If you specify multiple panes, they will appear one after another with splitters between them.
 
 The following base options are available for a pane:
 
 - [resizable](/Documentation/ApiReference/UI_Components/dxSplitter/Configuration/items/#resizable) (default: `true`)    
-If true, a handle appears at the side of the pane. Drag the handle to adjust the pane size.
+If true, a handle appears at the side of the pane. Drag the handle to adjust pane size.
 
 - [collapsible](/Documentation/ApiReference/UI_Components/dxSplitter/Configuration/items/#collapsible) (default: `false`)    
 If true, an arrow appears on the handle. Click the arrow to close the pane.
@@ -21,17 +21,17 @@ To configure the layout of the Splitter component, you can specify its [orientat
 Initial pane width/height.
 
 - [minSize](/Documentation/ApiReference/UI_Components/dxSplitter/Configuration/items/#minSize)    
-The minimum width/height for a resizable pane.
+Minimum width/height for a resizable pane.
 
 - [maxSize](/Documentation/ApiReference/UI_Components/dxSplitter/Configuration/items/#maxSize)    
-The maximum width/height for a resizable pane.
+Maximum width/height for a resizable pane.
 
 - [collapsedSize](/Documentation/ApiReference/UI_Components/dxSplitter/Configuration/items/#collapsedSize)    
 The width/height of a collapsible pane when collapsed.
 
-You can also place one Splitter inside another to create nested layouts. For this, use the pane's [splitter](/Documentation/ApiReference/UI_Components/dxSplitter/Configuration/items/#splitter) property.
+You can also place one Splitter inside another to create nested layouts. To do so, use the pane's [splitter](/Documentation/ApiReference/UI_Components/dxSplitter/Configuration/items/#splitter) property.
 
-Splitter panes can contain content of different types, from simple HTML markup to components. You can declare HTML markup inside the item tag or use the following properties to populate panes with content:
+Splitter panes can include different content types, from simple HTML markup to components. You can declare HTML markup inside the item tag or use the following properties to populate panes with content:
 
 - [itemTemplate](/Documentation/ApiReference/UI_Components/dxSplitter/Configuration/#itemTemplate)    
 Specifies a custom template for all panes.