Copy the following text and paste it into a text file, then save that file as "toolbarBindings.xml":
<bindings id="toolbarBindings">
<binding id="toolbar-primary" extends="chrome://global/content/bindings/toolbar.xml#toolbar-primary">
<content>
<xul:hbox class="toolbar-holder toolbar-primary-holder" flex="1" xbl:inherits="orient=tborient,buttonstyle">
<xul:hbox class="toolbar-button-box" flex="1">
<children/>
</xul:hbox>
<xul:image class="toolbar-primary-icon" xbl:inherits="buttonstyle"/>
</xul:hbox>
</content>
</binding>
</bindings>