<!DOCTYPE ui:UiBinder SYSTEM "http://dl.google.com/gwt/DTD/xhtml.ent">
<ui:UiBinder xmlns:ui="urn:ui:com.google.gwt.uibinder"
             xmlns:g="urn:import:com.google.gwt.user.client.ui"
             xmlns:v="urn:import:stroom.widget.button.client">
  <ui:style>
  .button {
  	position: absolute;
  }
  
  .textbox {
  	width: 100%;
    height: 100%;
  	padding-left: 20px;
    font-family: monospace;
  }
  </ui:style>
  <g:Grid styleName="stroom-control-grid" width="100%" height="100%">
    <g:row>
      <g:cell>Expression:</g:cell>
      <g:customCell>
        <g:FlowPanel width="100%" height="100%">
          <v:ImageButton ui:field="addFunction" title="Add Function"
            addStyleNames="{style.button}" />
          <g:TextArea ui:field="expression" addStyleNames="{style.textbox}" />
        </g:FlowPanel>
      </g:customCell>
    </g:row>
  </g:Grid>
</ui:UiBinder> 

<!DOCTYPE ui:UiBinder SYSTEM "http://dl.google.com/gwt/DTD/xhtml.ent">
<ui:UiBinder xmlns:ui="urn:ui:com.google.gwt.uibinder"
             xmlns:g="urn:import:com.google.gwt.user.client.ui"
             xmlns:v="urn:import:stroom.widget.button.client">
  <ui:style>
  .button {
  	position: absolute;
  }
  
  .textbox {
  	width: 100%;
    height: 100%;
  	padding-left: 20px;
    font-family: Roboto Mono;
  }
  </ui:style>
  <g:Grid styleName="stroom-control-grid" width="100%" height="100%">
    <g:row>
      <g:cell>Expression:</g:cell>
      <g:customCell>
        <g:FlowPanel width="100%" height="100%">
          <v:ImageButton ui:field="addFunction" title="Add Function"
            addStyleNames="{style.button}" />
          <g:TextArea ui:field="expression" addStyleNames="{style.textbox}" />
        </g:FlowPanel>
      </g:customCell>
    </g:row>
  </g:Grid>
</ui:UiBinder> 

Change monospace to Roboto Mono
Change monospace to Roboto Mono
