function isUnwrappable(node, options) {
        if (!isHtmlElement(node)) {
            return false;
        }

        if (!isInlineNode(node)) {
            return true;
        }

        if (!isEditable(node, options)) {
            return true;
        }

/*
        if (node.nodeType == 3 && options.ignoreWhiteSpace && !/[^\r\n\t ]/.test(node.data)
                && (isUnwrappable(node.previousSibling, options) || isUnwrappable(node.nextSibling, options))) {
            return true;
        }
*/

        return unwrappableTagNamesRegex.test(node.tagName);
    }
"An unwrappable node is an HTML element which may not be used where only
phrasing content is expected (not counting unknown or obsolete elements,
which cannot be used at all); or any Element whose display property computes
to something other than 'inline', 'inline-block', or 'inline-table'; or any
node whose parent is not editable."