Settings -> Translation -> DeepL key saves the user's own DeepL API key;
translation then asks DeepL first, else Google's free endpoint, else
MyMemory. Saving a key translates one sentence and says whether it works or
why not (a refused key, a used-up month, busy). Only the key's tag changes,
so the page keeps its scroll place. The key stays on this computer: backups
leave it out like the Civitai key.
DeepL stopped taking the key as an auth_key parameter in 2025, so a key put
in config.json by hand no longer worked. It now goes in the Authorization
header with a JSON body; targets are ZH-HANS and EN-US. When DeepL fails,
the answer carries deepl_error beside the other provider's translation.
Checked live: a made-up key is refused by DeepL's server and the dialog
says so; removing it switches back to Google.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>