he interior;
        // <<foo/bar>> is how you write it with a for,
        // not <foo/<bar>> or whatever.
        for(var i = 0; i < ltAlts.length; i++) {
            const lt = ltAlts[i];
            const match = /<(.*)>/.exec(lt);
            if(match) { ltAlts[i] = match[1]; }
        }
    }

    let forAlts;
    if(dfn.hasAttribute('data-dfn-for')) {
        forAlts = dfn.getAttribute('data-dfn-for')
            .split(",")
            .map(x=>x.trim());
    } else {
        forAlts = [''];
    }

 