/indra/newview/skins/default/xui/en/panel_toast.xml

<?xml version="1.0" encoding="utf-8" standalone="yes"?>
<!-- All our XML is utf-8 encoded. -->

<!-- Don't remove floater's height! It is needed for Overflow and Start-Up toasts!-->

<!-- 
     This floater is invisible. To make toast look like a floater we render wrapper_panel
     like a floater(draw shadows and so on). This is done with one purpose - make close button
     look like it is positioned out of floater and able to accept mouse clicks (see EXT-4246)
-->

<floater
 open_positioning="none"
 legacy_header_height="0"
 header_height="0"
 name="toast"
 title=""
 visible="false"
 layout="topleft"
 height="47"  
 width="310"
 left="0"
 top="0"
 background_visible="false"
 bg_opaque_image="Toast_Over"
 bg_alpha_image="Toast_Background"
 can_minimize="false"
 can_tear_off="false"
 can_resize="false"
 can_drag_on_left="false"
 can_close="false"
 can_dock="false"
 border_visible = "false"
 border = "false"
>
 <panel
  background_opaque="false"
  border_visible="false"
  background_visible="true"
  bg_opaque_image="Toast_Over"
  bg_alpha_image="Toast_Background"
  label="wrapper_panel"
  layout="topleft"
  left="0"
  name="wrapper_panel"
  top="7"
  height="40"
  follows="all" 
  translate="false"
  width="305">
  <!-- Don't remove this wiget! It is needed for Overflow and Start-Up toasts!-->
  <text
    clip_partial="true" 
   visible="false"
   follows="left|top|right|bottom"
   font="SansSerif"
   height="20"
   layout="topleft"
   left="20"
   name="toast_text"
   word_wrap="true"
   text_color="white"
   top="5"
   translate="false"
   use_ellipses="true"
   width="260">
    Toast text;
  </text>
 </panel>
  <button
    layout="topleft"
    top="0"
    right="310"
    width="17"
    height="17"
    follows="top|right"
    visible="false"
    enabled="true"
    mouse_opaque="false"
    name="hide_btn"
    label=""
    tab_stop="false"
    image_unselected="Toast_CloseBtn"
    image_selected="Toast_CloseBtn"
  />
</floater>