Gmail Contextual Gadget Not Visible in Gmail - google-apps-marketplace

Question

I am trying to develop one gmail gadget. I have prepared my gadget.xml file after reading all the required peoint mentioned in the google documents. But after that they ask to make a manifest file. But as far I have searched, now we don't need to prepare any manifest file. Now, we can prepare it through Google Apps Marketplace SDK. I have prepared a manifest here and saved it and enabled it from console.developers.google.com.
But after that also, I am not able to see my gadget in Gmail. Please any experienced developer help me in this problem. I trying to solve this problem from long time.
Here is my gadget.xml code:
<?xml version="1.0" encoding="UTF-8"?>
<Module>
<ModulePrefs author="Company Name" height="500" author_email="abc#example.com" author_location="India">
<Require feature="dynamic-height"/>
<Require feature="views" />
<Require feature="google.contentmatch">
<Param name="extractors">google.com:MessageIDExtractor</Param>
<Param name="extractors">google.com:SenderEmailExtractor</Param>
</Require>
</ModulePrefs>
<Content type="html" view="card">
<![CDATA[
<p> Pragmatic Odoo Gmail Integration</p>
<script>console.log('Hello from gadget.')</script>
]]>
</Content>
</Module>
Here is my Google Apps Marketplace SDK settings for gadget:
enter image description here

Answer 1

Pay attention to below hints:
Add an app to chrome web store and link it to your Google project, which you describe contextual gadget, with project ID.Here's a sample of web store manifest.json:
{
"manifest_version": 2,
"name": "Sample App",
"short_name": "Dev",
"version": "1.0.0",
"default_locale": "en",
"description": "Sample app",
"app" : {
"launch" : {
"web_url" : "http://yourcompany.com"
}
},
"icons": {
"128": "icons/128x128-icon.png",
"16": "icons/16x16-icon.png"
},
"container": ["DOMAIN_INSTALLABLE"],
"api_console_project_id": "your-project-id"
}
After publish this app, add it to test Google Domain. Since your gadget is in development stage so, don’t publish your app to Public. There are different "Visibility options" that you can choose.
To disable cache use nogadgetcache=1 (e.g. https://mail.google.com/?nogadgetcache=1)
Login with admin account which you want to test it, otherwise take more time to update manifest.
After Modify “Google Apps Marketplace SDK” click on “Test Installation Flow” to be sure there is no new permission.
I did these part and works for me:
Define google.com:MessageIDExtractor as first extension, however you don’t need that.
I recommend that select every scopes which you want to use in other
extensions here! I don’t know why put it seems the google just ask
these permission for my gadget
Define Param extractor in gadget.xml separately not with comma:
<Require feature="google.contentmatch">
<Param name="extractors">
google.com:MessageIDExtractor
</Param>
<Param name="extractors">
google.com:SenderEmailExtractor
</Param>
</Require>