We are currently working on an official announcement / documentation that got delayed by the Holidays. Regarding the attachments limits I can give insight to why as I did everything I could to allow the maximum size based on existing limitations in other systems:
In order to maximize the attachment size limit it's more complicated than one simple limit. It's actually three limits:
Approvals backend service
Combinedattachmentsize (sum of allattachmentsizes unencoded) is 50MB.
We set thislimit.
Common Data Service
Individualattachmentsizelimitdefaults to 5MB
A CDS admin can change this by going into CDS -> Email Configuration settings -> Set file sizelimitforattachments
The internal emailing service we use:
Combinedattachmentsize is 5MB
If thislimitis exceeded thenattachments do not show up in theapprovalemails and instead an "attachments are too big" message shows up with a link to see them in theApprovalcenter.
Everyone is most likely hitting the Common Data Service limit of 5MB which they should contact their admin to increase. Common Data Service allows the limit to be set to a maximum of ~132MB for an individual attachment.
Could you please provide the url of the flow run where you are hitting this issue so that I can investigate for you?
The known issues I am currently working on fixing:
Files with empty content causes sending approval emails to fail to a limitation with the internal emailing service.
Approval actions don't display the proper failure message when creating approvals with attachments that are banned by the Common Data Service configuration.
@TCambs the attachments are being pulled from a SharePoint list that is populated by a PowerApp. Not sure if that makes any difference, but thought I'd point that out.
Looks like a regression, I can reproduce the problem. It's failing for a size over 8MB (for a reason unrelated to any limits). I will work on a fix along side the other known issues immediately. Thank you for bringing this to my attention.
This feature is completed - you can read more here: https://flow.microsoft.com/blog/file-attachments-in-approval-flows/