Re-checking "Applies to administration pages" in the settings screen does not update the breadcrumb

Shoot, the error is the same as the one on my local:

1) Drupal\Tests\easy_breadcrumb\Functional\EasyBreadcrumbAdminRouteToggleTest::testReEnablingAdminRoutesRestoresBreadcrumb
Exception: User warning: Trying to overwrite a cache redirect for "entity_view:block:breadcrumb:[languages]=en:[route]=system.admin35786c7117b4e38d0f169239752ce71158266ae2f6e4aa230fbbb87bd699c0e3:[theme]=stark:[user.permissions]=is-admin" with one that has nothing in common, old one at address "languages:language_interface, theme, user.permissions, route, languages" was pointing to "url.path.parent, url.path.is_front", new one points to "url".

Unassigning from myself to hear from Greg on his thoughts for next steps.

I hooked into the configuration save event to invalidate a custom tag that is added in the applies() method when the configuration for applying to admin routes is disabled.

User warning: Symfony\Component\DependencyInjection\Exception\ServiceNotFoundException: You have requested a non-existent service "cache_context.easy_breadcrumb". in

This happens when you disable the admin crumbs and view a page

Oof, this is a real doozy. I'll have to come back to it. Or maybe someone else can figure it out.

What I've done this time is:

Added a cache context and an event subscriber for config save.

In the applies() method, I add the cache context.

In the context subscriber, using the same logic for checking the "applies to admin paths" config and for checking to see if the current request is an admin path as is in the applies() method, I return a particular tag.

Then, in the config save event subscriber, the tag is invalidated.

Fresh brain, new day. Turns out we don't need a subscriber. The context plugin is all that's needed.

✅ Tested and works — MR !231. The fresh-brain call in was right: the context plugin on its own is enough, no config-save subscriber needed, and none of the earlier symptoms come back — no cache-redirect warning, and no missing cache_context.easy_breadcrumb service when admin crumbs are disabled.

OMG, yes, Greg. That's how I feel too. Thanks also @csakiistvan. I'll work on merging this in now.

Nice to work with you guys <3

you too, csakiistvan. Community is so important