Man pages matching name curlopt_http_content_decoding in section 3:

CURLOPT_HTTP_CONTENT_DECODING.3.en	debian 10 / libcurl4-doc
CURLOPT_HTTP_CONTENT_DECODING.3.en	debian 11 / libcurl4-doc
CURLOPT_HTTP_CONTENT_DECODING.3.en	debian 12 / libcurl4-doc