Google authentication and not being able to edit attachments directly from WEBCON BPS Portal forms.

Environments without a Windows domain can still work with WEBCON BPS as long as it is configured to use Google authentication.

However, such a configuration will not allow attachments to be edited directly from the form viewed in WEBCON BPS Portal and using the desktop version of Microsoft Office.

To edit files on the form, WEBCON BPS uses WebDav protocols. Microsoft does not support using WebDav protocols in desktop products while using Google Identity as the external authentication provider.

Trying to edit a file in such a scenario will result in a “Your organization's policies are preventing us from completing this action for you” type message. Microsoft supports Google Identity as an external provider for Office365 online solutions only.

Microsoft Office online is not currently supported as a method of editing attachments on forms in the WEBCON BPS system.

Official Microsoft stance on external identity providers in Office products:

Add Google as an identity provider for B2B - Azure AD | Microsoft Docs
https://docs.microsoft.com/en-us/azure/active-directory/external-identities/google-federation

Set up sign-up and sign-in with a Google account - Azure AD B2C | Microsoft Docs
According to these Microsoft articles, Office 2016 and 2019 are not supported to work on the scenario required. Google identity provider only works with Office 365 environments.
https://docs.microsoft.com/en-us/azure/active-directory-b2c/identity-provider-google?pivots=b2c-user-flow