Outlook add-in API requirement set 1.8 is missing

[Levure]

Hello,

I am trying to deploy an Outlook (Office365) add-in which uses Outlook add-in API requirement set 1.8.
The manifest.xml files declares this requirement using

  <Requirements>
    <Sets>
      <Set Name="Mailbox" MinVersion="1.8" />
    </Sets>
  </Requirements>

but the manifest.xml file is rejected by Office 365 Admin - Add-in deployement tool.

When validating the manifest file using npx office-addin-manifest validate .\manifest.xml
I get this error :

No supported Office products detected: There are no platforms which fulfil the requirements specified in the manifest. The most common reasons for this failure are issues in the Requirements section. Please review the manifest and try again. (link: undefined)

It seems like that the Outlook add-in API requirement set 1.8 is missing in the https://github.com/OfficeDev/Office-Js-Requirement-Sets/blob/master/mapping/requirements_officejs.json file.

Could this missing entry be the cause of the add-in manifest file rejection by the Office 365 Admin - Add-in deployement tool ?

Thanks in advance !