[KevinH]

You would have to rebuild from source yourself after modifying the relevant Toolbars sections in Sigil/src/Form_Files/main.ui

It is a strict XML file so be careful how you edit it (keep opening and closing pairs, etc). There is also a Qt based gui editor tool that could be used to edit that xml file.

In the next release we could split some of the larger Toolbar area groups to make them smaller to give more granular controls.

See after line 457 in main.ui to this clump of code:

<widget class="QToolBar" name="toolBarTextManip">
   <property name="windowTitle">
    <string>Edit</string>
   </property>
   <attribute name="toolBarArea">
    <enum>TopToolBarArea</enum>
   </attribute>
   <attribute name="toolBarBreak">
    <bool>false</bool>
   </attribute>
   <addaction name="actionUndo"/>
   <addaction name="actionRedo"/>
   <addaction name="separator"/>
   <addaction name="actionCut"/>
   <addaction name="actionCopy"/>
   <addaction name="actionPaste"/>
   <addaction name="separator"/>
   <addaction name="actionXEditor"/>
   <addaction name="separator"/>
   <addaction name="actionFind"/>
  </widget>

Then delete the addaction lines that you would guess from this clump.