Visio Web Access will be deprecated onSeptember 30, 2021
No active development work will happen towards Visio services starting September 30, 2021.
Visio Web Access (aka Visio Services) allows online viewing of Visio diagrams stored on SharePoint Online and SharePoint On-Premise.
Visio Services render Visio documents in a Web browser without having Visio or Visio viewer installed on a local computer
It supports embedding of Visio Web Access Web Part in SharePoint let you add diagrams to a SharePoint page.
Embedded Web Parts can be linked to data sources so that when data changes, the visuals (shapes, text, etc.) change too
Web Parts can also be driven programmatically using the JS API
Recommended Steps for Customers Using Visio Web Services on SharePoint Online
Microsoft recommends that customers start upgrading toVisio Online. Visio Online enables high fidelity viewing, sharing, and collaboration on the web browser full page without installing the client for all Office 365 licenses. It also supports embedding Visio diagrams in SPO by using File Viewer Web Part and iFrames along with JS API programmability.
In addition, Visio Online supports richer scenarios such as find, pan/zoom, and Power BI integrated dashboards among other things. Moving to Visio Online will enable you to take advantage of the latest product innovations and ensure latest performance and reliability improvements that come from Microsoft’s Visio team.
Post the end of support period:
Visio files from SPO will continue to open in Visio Online, but the user will not be able to switch to Legacy Service
If you were using the Visio Services Web Access for web page viewing, you will need to resave your .VDW files into the new file format .VSD/.VSDX
If you were using Visio Web AccessWeb Part, you will have to migrate themVisio OnlineFile Viewer Web Part to embed Visio documents in SPO
If you were using Visio Services Web AccessWeb Partswith JS APIs, you will have to migrate them to iFrame withnewJS APIs in Visio Online to stop them from working
For more information about this deprecation and instructions related to switching to Visio Online, check outthis blog.