When the user profile language is french or Italian, the Regular expression configuration menu does not display.
If I examine the html generated code, the div "tabs" is not visible :
<div id="tabs" class="tabs" >
when i select any other langage, the div is like :
<div id="tabs" class="tabs ui-tabs ui-widget ui-widget-content ui-corner-all" style="visibility: visible;">
Maybe some translation are missing for french and italiano.