Constant MAX_RENDER_HTML_BYTES 

pub const MAX_RENDER_HTML_BYTES: usize = crate::feed::MAX_CONTENT_HTML_BYTES /* 2_097_152usize */;

The longest stored body render will sanitize: ingest’s own stored bound (feed::MAX_CONTENT_HTML_BYTES), so no body ingest wrote is ever refused. Only a row that skipped feed.rs, or one from before the bound existed (#224), can be longer, and such a row is not given to the sanitizer at all.