[update] correct and complete docs for v5.2

Author: mafanya23

docs/assets/show_columns_context_menu.png

@@ -359,13 +359,15 @@ The [default context menu](/#context-menu) has the following structure:
   - the separator
   - the *Unfreeze columns* menuItem (id: "unfreeze-cols")
   - the *Freeze up to column [id]* menuItem (id: "freeze-cols")
+  - the *Show columns* menuItem (id: "show-cols")
   - the *Hide column(s) [id]* menuItem (id: "hide-cols")
 - the **Rows** menuItem (id: "rows")
   - the *Add row* menuItem (id: "add-row")
   - the *Remove row* menuItem (id: "remove-row")
   - the separator
   - the *Unfreeze rows* menuItem (id: "unfreeze-rows")
   - the *Freeze up to row [id]* menuItem (id: "freeze-rows")
+  - the *Show rows* menuItem (id: "show-rows")
   - the *Hide row(s) [id]* menuItem (id: "hide-rows")
 - the **Sort** menuItem (id: "sort")
   - the *Sort A to Z* menuItem (id: "asc-sort")

docs/assets/show_rows_context_menu.png

@@ -53,7 +53,7 @@ The new release introduces some changes to the freezing/unfreezing functionality
 - The problem with editing a large spanned table
 - The error that occurred on undoing an action in a cell 
 - The error that occurred on entering/editing a cell with the IF formula
-- Th script error that occurred after cutting and pasting a link
+- The script error that occurred after cutting and pasting a link
 - The issue with changing the text alignment during export/import of an .xlsx file
 - The issue with Spreadsheet losing focus after some actions
 - Performance improvements

docs/customization.md

@@ -124,7 +124,7 @@ To freeze rows up to a certain row, take the following steps:
 
 ### Unfreezing rows
 
-(*In the images below rows are frozen up to the "5" row*)
+(*In the images below rows are frozen up to the row 5*)
 
 To unfreeze rows, take one of the following steps:
 
@@ -136,7 +136,7 @@ To unfreeze rows, take one of the following steps:
 
 ![Unfreezing rows menu](assets/unfreeze_rows_menu.png)
 
-- or right-click any row/cell in the row and choose *Rows -> Unfreeze rows*
+- or right-click any cell and choose *Rows -> Unfreeze rows*
 
 ![Unfreezing rows context menu](assets/unfreeze_rows_context_menu.png)
 
@@ -162,7 +162,7 @@ To freeze columns up to a certain column, take the following steps:
 
 ### Unfreezing columns
 
-(*In the images below columns are frozen up to the "D" column*)
+(*In the images below columns are frozen up to the column D*)
 
 To unfreeze columns, take one of the following steps:
 
@@ -174,7 +174,7 @@ To unfreeze columns, take one of the following steps:
 
 ![Unfreezing columns menu](assets/unfreeze_columns_menu.png)
 
-- or right-click any column/cell and choose *Columns -> Unfreeze columns*
+- or right-click any cell and choose *Columns -> Unfreeze columns*
 
 ![Unfreezing columns context menu](assets/unfreeze_columns_context_menu.png)
 
@@ -198,10 +198,20 @@ To hide a row, take the following steps:
 
 ### Showing rows
 
-To show a hidden row/rows, click the "arrows" icon that appears in the rows header instead of the hidden row/rows. In the image below the rows 8 and 11 are hidden:
+To show hidden rows, take one of the following steps:
+
+- either click the "arrows" icon that appears in the rows header instead of the hidden row/rows
+
+(*In the image below the rows 8 and 11 are hidden*)
 
 ![Showing rows](assets/show_rows.png)
 
+- or select rows or several cells so that the hidden rows were included into the selection, right-click to call the context menu and choose *Rows -> Show rows*
+
+(*In the image below the row 8 is hidden*)
+
+![Showing rows context menu](assets/show_rows_context_menu.png)
+
 ### Hiding columns
 
 To hide a column, take the following steps:
@@ -220,8 +230,18 @@ To hide a column, take the following steps:
 
 ### Showing columns
 
-To show a hidden column/columns, click the "arrows" icon that appears in the columns header instead of the hidden column/columns. In the image below the columns C and E are hidden:
+To show hidden columns, take one of the following steps:
+
+- either click the "arrows" icon that appears in the columns header instead of the hidden column/columns
+
+(*In the image below the columns C and E are hidden*)
 
 ![Showing columns](assets/show_columns.png)
 
+- or select columns or several cells so that the hidden columns were included into the selection, right-click to call the context menu and choose *Columns -> Show columns*
+
+(*In the image below the column C is hidden*)
+
+![Showing columns context menu](assets/show_columns_context_menu.png)
+