aseprite/data/widgets/canvas_size.xml

<!-- ASEPRITE -->
<!-- Copyright (C) 2001-2013 by David Capello -->
<gui>
  <box vertical="true" id="main_box">
    <box horizontal="true">
      <box vertical="true" homogeneous="true">
        <label text="Left:" />
        <label text="Right:" />
      </box>
      <box vertical="true" homogeneous="true">
        <entry text="0" id="left" maxsize="32" maxwidth="64" tooltip="Columns to be added/removed in the left side.&#10;Use a negative number to remove columns." />
        <entry text="0" id="right" maxsize="32" maxwidth="64" tooltip="Columns to be added/removed in the right side.&#10;Use a negative number to remove columns." />
      </box>
      <box vertical="true" homogeneous="true">
        <label text="Top:" />
        <label text="Bottom:" />
      </box>
      <box vertical="true" homogeneous="true">
        <entry text="0" id="top" maxsize="32" maxwidth="64" tooltip="Rows to be added/removed in the top side.&#10;Use a negative number to remove rows." />
        <entry text="0" id="bottom" maxsize="32" maxwidth="64" tooltip="Rows to be added/removed in the bottom side.&#10;Use a negative number to remove rows." />
      </box>
    </box>
    <separator horizontal="true" />
    <box horizontal="true">
      <box horizontal="true" expansive="true" />
      <box horizontal="true" homogeneous="true">
        <button text="&amp;OK" closewindow="true" id="ok" magnet="true" width="60" />
        <button text="&amp;Cancel" closewindow="true" />
      </box>
    </box>
  </box>
</gui>