Add notes on support around site templates

Author: VesaJuvonen

docs/solution-guidance/modern-experience-customizations-customize-pages.md

@@ -33,6 +33,7 @@ These customizations are currently not supported for "modern" pages:
  - Custom JavaScript embedded via user custom actions (see note on *SharePoint Framework Extensions*)
  - Custom master pages (more extensive branding will be supported later using alternative options)
  - Minimal Download Strategy (MDS)
+ - Modern pages inside of the a Site Template package (Save site as a template)
 
 > [!NOTE]
 > - We don't recommend combining "modern" page functionality with "classic" SharePoint publishing portals. By default, the "modern" page functionality is not enabled on "classic" SharePoint publishing portals.

docs/solution-guidance/modern-experience-customizations-customize-sites.md

@@ -56,6 +56,7 @@ In numerous areas on the "modern" team sites, the typical customizations are not
 - Ability to control available subsite template options.
 - "Classic" publishing features (WCM).
 - Activation of community feature or creation of community subsites under "modern" team site.
+- Saving site as a template. Also not supported for sub sites in site collections which root site is a group associated team site or communication site.
 
 Because "modern" team sites also have scripting capabilities disabled (it's a so called NoScript site), numerous areas cannot be customized. The impact of NoScript is the same for "modern" or "classic" sites. "Modern" sites have NoScript enabled by default, meaning that scripting capabilities are not available. However, it is possible and supported to disable NoScript settings in both "modern" and "classic" sites to further enable some capabilities.