What happened?

Description

In a multi-site Craft 5 install with multiple site groups, the site breadcrumb link is missing its href attribute:

Steps to reproduce

1. Create at least two site groups.
2. Visit /admin/entries, and confirm that the site crumb doesn't have a href attribute.

Expected behavior

The site crumb link should probably link to the active site, regardless of the number of site groups.

Actual behavior

The site crumb link only has a href attribute when there is only a single site group.

Craft CMS version

5.0.4

PHP version

No response

Operating system and version

No response

Database type and version

No response

Image driver and version

No response

Installed plugins and versions

None