Improve System Summary Links to Show Data for All Site IDs

[elvmp]

Description:

Currently, clicking on links in the System Summary (e.g., Segments, Heatmaps, Goals, Custom Reports, Forms, etc.) only displays data for the currently selected site ID. This behavior is limiting for superusers managing multiple websites, as they need to manually switch between sites to see a complete overview.

Expected Behavior

Clicking on a link in the System Summary should provide an overview of the corresponding items (segments, heatmaps, goals, etc.) across all site IDs, or at least allow filtering by site ID.

Current Behavior

Clicking on a link in the System Summary only displays data for the currently selected site.
To see data from a different site, users must manually switch site IDs, which is inefficient for managing multiple sites.

Suggested Improvement

Modify the System Summary links to show a complete list of all segments, heatmaps, goals, custom reports, forms, etc. across all sites.
Provide a filter to allow switching between site-specific and global overviews.
Improve navigation for superusers who need a complete overview of Matomo's tracking setup.