帮助！我一遍又一遍地看着它，它只是不会加载。我应该看到它显示在每封电子邮件上，但没有。我错过了什么？
<?xml version="1.0" encoding="UTF-8" ?>
<ApplicationManifest xmlns="http://schemas.google.com/ApplicationManifest/2009">
<!-- Support info to show in the marketplace & control panel -->
<Support>
<!-- URL explaining how customers get support. -->
<Link rel="support" href="http://example.com" />
</Support>
<Edition id="SlidersExtractor"></Edition>
<!-- Name and description pulled from message bundles -->
<Name>Sliders 2</Name>
<Description>Sliders</Description>
<!-- EXTRACTOR -->
<Extension id="SlidersExtractor" type="contextExtractor">
<Name>Sliders</Name>
<Url>google.com:SubjectExtractor</Url>
<Triggers ref="Sliders"/>
<Scope ref="emailSubject"/>
<Container name="mail"/>
</Extension>
<!-- GADGET -->
<Extension id="Sliders" type="gadget">
<Name>Sliders Gmail contextual gadget</Name>
<Url>http://hosting.gmodules.com/ig/gadgets/file/117105461644591440890/sliders.xml</Url>
<Container name="mail"/>
</Extension>
<!-- SCOPE -->
<Scope id="emailSubject">
<Url>tag:google.com,2010:auth/contextual/extractor/SUBJECT</Url>
<Reason>This application searches the Subject:"</Reason>
</Scope>
</ApplicationManifest>
小工具：
<?xml version="1.0" encoding="UTF-8"?>
<Module>
<ModulePrefs title="Sliders Gadget"
description="Matches emails"
height="20"
author="me"
author_email="james@example.com"
author_location="everywhere">
<!-- Declare feature dependencies. -->
<!-- This one is not specific to Gmail contextual gadgets. -->
<Require feature="dynamic-height"/>
<Require feature="google.contentmatch">
<Param name="extractors">
google.com:SubjectExtractor
</Param>
</Require>
</ModulePrefs>
<!-- Define the content type and display location. The settings
"html" and "card" are required for all Gmail contextual gadgets. -->
<Content type="html" view="card">
<![CDATA[
Hello Sliders 2/18
]]>
</Content>
</Module>