backstage

When you click on the File button in the top left corner you will see a collection of tabs and buttons called Backstage.
The icons, tabs and buttons are slightly different between the different versions.
There is no StartFromScratch option for backstage.

<customUI>

<backstage>

<tab>

<firstColumn>

<group>

<ribbon>

<commands>

Children

Excel

<customUI xmlns="http://schemas.microsoft.com/office/2009/07/customui">

<backstage>

<tab idMso="PlaceTabHome" label="Home" visible="false"/>

<tab idMso="TabOfficeStart" label="New" visible="false"/>

<tab idMso="TabRecent" label="Open" visible="false"/>

<button idMso="ShareDocument" label="Share" visible="false"/>

<button idMso="OfficeExtensionsGetAddinsButtonOnBackstageBelowOpenDivider" label="Get Add-ins" visible="false"/>

<tab idMso="TabInfo" label="Info" visible="false"/>

<button idMso="FileSave" label="Save" visible="false"/>

<tab idMso="TabSave" label="Save As" visible="false"/>

<tab idMso="TabPrint" label="Print" visible="false"/>

<tab idMso="TabPublish" label="Export" visible="false"/>

<button idMso="FileClose" label="Close" visible="false"/>

<tab idMso="TabHelp" label="Account" visible="false"/>

<button idMso="ApplicationOptionsDialog" label="Options" visible="false"/>

</backstage>

</customUI>

These buttons were removed (Save As - FileSaveAs, Open - FileOpen, History - HistoryTab, Feedback - OfficeFeedback, Exit - FileExit).
These tabs were removed (Publish - Publish2Tab, Feedback - TabOfficeFeedback).

Word

<customUI xmlns="http://schemas.microsoft.com/office/2009/07/customui">

<backstage>

<tab idMso="PlaceTabHome" label="Home" visible="false"/>

<tab idMso="TabOfficeStart" label="New" visible="false"/>

<tab idMso="TabRecent" label="Open" visible="false"/>

<button idMso="ShareDocument" label="Share" visible="false"/>

<button idMso="OfficeExtensionsGetAddinsButtonOnBackstageBelowOpenDivider" label="Get Add-ins" visible="false"/>

<tab idMso="TabInfo" label="Info" visible="false"/>

<button idMso="FileSave" label="Save" visible="false"/>

<tab idMso="TabSave" label="Save As" visible="false"/>

<tab idMso="TabPrint" label="Print" visible="false"/>

<tab idMso="TabPublish" label="Export" visible="false"/>

<button idMso="DigitalPrint" label="Transform" visible="false"/>

<button idMso="FileClose" label="Close" visible="false"/>

<tab idMso="TabHelp" label="Account" visible="false"/>

<button idMso="ApplicationOptionsDialog" label="Options" visible="false"/>

</backstage>

</customUI>

PowerPoint

<customUI xmlns="http://schemas.microsoft.com/office/2009/07/customui">

<backstage>

<tab idMso="PlaceTabHome" label="Home" visible="false"/>

<tab idMso="TabOfficeStart" label="New" visible="false"/>

<tab idMso="TabRecent" label="Open" visible="false"/>

<button idMso="ShareDocument" label="Share" visible="false"/>

<button idMso="OfficeExtensionsGetAddinsButtonOnBackstageBelowOpenDivider" label="Get Add-ins" visible="false"/>

<tab idMso="TabInfo" label="Info" visible="false"/>

<button idMso="FileSave" label="Save" visible="false"/>

<tab idMso="TabSave" label="Save As" visible="false"/>

<tab idMso="TabPrint" label="Print" visible="false"/>

<tab idMso="TabPublish" label="Export" visible="false"/>

<button idMso="FileClose" label="Close" visible="false"/>

<tab idMso="TabHelp" label="Account" visible="false"/>

<button idMso="ApplicationOptionsDialog" label="Options" visible="false"/>

</backstage>

</customUI>

Outlook

Info
Open & Export
Save As
Save Attachments
Print
Close
Office Account
Options
Exit