I have a User login block that's not visible, configurable or removable on my development server for some reason, even though it works fine on production (I'm managing config using standard D8 config sync).
This seems to apply to any User Login blocks - if I place further instances (without any role/page restrictions) they aren't visible, and I get Access Denied - as user 1 - when trying to disable them.
Disable (and Devel) are the only operations visible in Block Layout on this server for this type of block. (Obviously, the standard behavior is you can configure a User Login block once placed.)
Yet I can place and later reconfigure a Search form, for example.
- I've compared the block's .yml file (in config/sync) between both servers and it's identical.
- I've tried removing the problem blocks (by exporting the config, deleting the block file then syncing /config/sync again) and replacing them.
- I've rebuilt permissions - /admin/reports/status/rebuild
Any suggestions for debugging (in xdebug etc)? Is there a way I can trace if a contrib module is altering the permissions?