Scripting capability in Solution Studio is related to Custom Script option in the SharePoint admin settings. It is needed for creating or updating Solutions. The dialog for enabling scripting capabilities will appear on creating solution on the new site collection.
The other ways how to enable scripting capabilities:
- If you need to enable custom scripts manually for a certain site, you can use the following Microsoft PowerShell commands:
Using the SharePoint Online Management Shell
Connect-SPOService -Url "https://<SPO tenant name>-admin.sharepoint.com" -Interactive
Set-SPOsite "https://<SPO tenant name>.sharepoint.com/sites/<Site name>" -DenyAddAndCustomizePages 0
or using PnP Powershell
Connect-PnPOnline -Url "https://<SPO tenant name>.sharepoint.com/sites/<Site name>" -Interactive -ClientId <client id of your Entra ID Application Registration>
Set-PnPTenantSite -Identity "https://<SPO tenant name>.sharepoint.com/sites/<Site name>" -DenyAddAndCustomizePages:$false
Hint: To run this commands you have to be SharePoint Admin (Site Owner is not enough)
This will allow adding custom scripts to the given site.
For more information also see the following MS article:
Allow or prevent custom script