You can set <updategeometry> to false in Edit widget's config:
<?xml version="1.0" ?>
<!-- If compiling this widget, make sure to add -keep-all-type-selectors=true to your compiler arguments in the FB project properties. -->
<configuration>
<createoptions>
<polygondrawtools>polygon,freehandpolygon,extent,autocomplete</polygondrawtools>
<polylinedrawtools>polyline,freehandpolyline,line</polylinedrawtools>
</createoptions>
<addfeatures>true</addfeatures>
<deletefeatures>true</deletefeatures>
<toolbarvisible>true</toolbarvisible>
<toolbarcutvisible>false</toolbarcutvisible>
<toolbarmergevisible>false</toolbarmergevisible>
<toolbarreshapevisible>false</toolbarreshapevisible>
<updategeometry>false</updategeometry>
<updateattributes>true</updateattributes>
</configuration>