This is an announcement of a new feature added to AMOS right now. Strings in the langconfig component cannot be edited any more.
As many of you know, the strings in the langconfig component are somewhat special. Their values are often not printed directly in the user interface. Instead, they affect how Moodle handles various localisation aspects. Things like date/time formatting strings, decimal separator character, ISO codes or the directionality of the given language are defined this way.
As you can imagine, bad things can happen when the language pack is not configured correctly. And it happens.
Attempting to minimise the chance of unintentional breakage of Moodle installations through misconfigured language packs, a new capability was introduced into AMOS to edit the strings in the langconfig component. The intention is that the AMOS site administrators and translation coordinators only (read: Helen and Koen) will be the ones to set up and edit language pack configuration. All other users will see the strings in the read-only mode with the note "No permission to edit language pack configuration".
If you need to change your language configuration, please raise a new MDLSITE issue with the component set to lang.moodle.org with your request and reasoning.
Thank you for understanding and all your valuable contributions to Moodle!