Unfortunately that add-on is not available for Cloud, and I don't believe there's anything similar available.
My suggestion is to get in touch with the Send email to Page developers, so they can work with Atlassian Connect team, and develop this add-on using Atlassian framework, and this way it will be available for Confluence Cloud.
Hi Atlassian Community! This is Teresa from the Jira Service Desk team. On June 19th, I’ll be hosting a webinar “Asset Management: The Role of Context in ITSM” with Atlassian Partne...
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