Problem description: 
Format Text Toolbar hight is a little bigger than the hight of other toolbars, what causes an ugly jumping of page contents

Steps to reproduce:
1. In a blank new Draw document in {Tools ► Options ► LibreOffice
   ► View} select Icon size = small and Style = Tango 
2. Into doucment insert a Text box with text "Textbox" and a 
   smiley
3. Make sure that you have the default toolbar places:
   Below Menu bar the Standard Toolbar
   Below Standard Toolbar the Text Format Toolbar, 
   At same plase as Text Format Toolbar the Line Format Toolbar
   if a line is selected
   Toolbars docked, but position not locked
4. Now single click to select smiley
   Lines Format Toolbar is visible
5. Now double click Text Box to select some characters in it
   Text Format Toolbar is visible
6. Return to step 4

Doing the loop 4 ... 6 you will see that in step 4 the horizontal ruler above the page contents and the page contents will move up a little fraction of a millimeter, and in step 5  the horizontal ruler above the page contents and the page contents will move down  a little fraction of a millimeter. Reason is that the hight of "Format Text" Toolbar is a little bigger than the hight of the Line Format Toolbar.

Conspicuous detail: the riffled vertical bar at the left end of the toolbar contains 5 dark dots in "Format Line " Toolbar, but 6 dots "Format Text" Toolbar
              
Not a big thing, but annoying if you often switch between Text Format Toolbar and other Format toolbar
Operating System: Windows 7
Version: 4.2.4.2 release