[5.x]: Entry duplication ignores site-specific Matrix field values and propagates content across sites #18659
Description
What happened?
Description
When duplicating an entry in a multi-site Craft CMS setup, content from a Matrix field is taken from one site (in a different site group) and applied to all other sites.
This happens even though the field and entry are configured to be site-specific.
Steps to reproduce
- Create a new site within a site group
- Enable the relevant section (in this case "home") for the new site
- Ensure existing entries in that section have different Matrix content per site
- Inspect the Matrix field content across the sites
Expected behavior
- Each site retains its own Matrix content
- Duplication should preserve per-site differences
- No content should be copied across unrelated sites or site groups
Actual behavior
- Matrix content from one site is selected (appears arbitrary or last-used)
- That content is then applied to all sites
- Site-specific content is overwritten
Additional Notes
- The issue persists regardless of propagation method
- Another Matrix field on the same entry, configured with "Save entries to other sites in the same site group", behaves correctly and does not exhibit this issue
Key Concern
This appears to ignore Craft’s translation behavior entirely, since:
- The field should store per-site values
- Yet duplication results in a single site's content being broadcast to all sites
Images showing the issue
The content is taken from "Noviso Oven NL" across all sites containing the banner matrix.
Craft CMS version
5.9.17
PHP version
8.3
Operating system and version
No response
Database type and version
mysql 8.0
Image driver and version
No response