Updates to custom scripting in sites and Classic Publishing site creation

Custom scripting will be disabled by default for certain SharePoint Online templates starting September 15, 2025. Users can manage site property bag values without enabling custom scripting. Creation of new classic publishing site collections and activation of publishing features will be restricted. Existing sites remain unaffected. We are implementing the following changes to custom scripting and classic publishing in SharePoint Online. 1. Disablement of custom scripting Custom scripting will be disabled by default (setting DenyAddAndCustomizePages to 1 or $true) for sites created with the following templates: BLANKINTERNETCONTAINER#0 = Classic Publishing Portal Site CMSPUBLISHING#0 = Classic Publishing Site BLANKINTERNET#0 = Classic Publishing Site Blank CSPCONTAINER#0 = SharePoint Embedded Site Refer to this documentation to learn more about the security considerations of ungoverned scripting. 2. Ability to set site property bag valued without requiring custom scripting enablement. Users no longer need to set DenyAddAndCustomizePages to $false or 0 (i.e. enable custom scripting) in a site to manage site property bag values. We have introduced a new AllowWebPropertyBagUpdateWhenDenyAddAndCustomizePagesIsEnabled setting at the site level and at the tenant level to allow adding/managing site property bag values. Please see documentation here for tenant level setting and here for the site level setting.  3. Classic publishing sites creation and feature activation changes Users will no longer be able to create new classic publishing related site collections or activate publishing features in existing site collections. This applies to both UX and API interactions. Sites collections with the following templates cannot be created: BLANKINTERNETCONTAINER#0 = Publishing Portal Site CMSPUBLISHING#0 = Publishing Site BLANKINTERNET#0 = Publishing Site Blank ENTERWIKI#0 = Enterprise Wiki SRCHCEN#0 = Enterprise Search Center SPSSITES#0 = Site Directory SPSNHOME#0 = News Home Site PRODUCTCATALOG#0 = Product Catalog SPSREPORTCENTER#0 = Report Center SPSTOPIC#0 = Topic Area Template Existing classic publishing enabled site collections are unaffected and can continue regular usage, including creation of sub sites. When this will happen Both changes, the extended custom scripting governance and the new classic publishing restrictions, will take effect starting September 15, 2025. How this will affect your organization When custom scripting is disabled in classic publishing sites, users will no longer […]

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