In the context of SharePoint Online, what is the significance of enabling 'Limited-access user permission lockdown mode' at the site collection level?

Enabling 'Limited-access user permission lockdown mode' at the site collection level in SharePoint Online enhances security by restricting the ability of users with 'limited access' permissions to browse the site collection unnecessarily. 'Limited access' is a permission level automatically granted to users when they are given direct access to a specific item (like a file or folder) within a SharePoint site, but not to the site itself. Without lockdown mode enabled, these users could potentially navigate to other parts of the site collection through various means, even though they don't have explicit permissions to those areas. Enabling 'Limited-access user permission lockdown mode' prevents these users from seeing or accessing anything beyond the specific item they were granted access to. This is particularly important for compliance and security-sensitive environments where minimizing unintended data exposure is critical. For example, if an external auditor is given access to a single document in a document library, enabling lockdown mode ensures that they cannot browse the rest of the document library or any other part of the site collection. This setting is a site collection-level setting and affects all sites and subsites within that site collection. It's an important security measure for organizations looking to strictly control access to sensitive information in SharePoint Online.