// ==UserScript==
// @name		   EnableOldAddonInstall
// @namespace	   mtamaki.com
// @description    EnableOldAddonInstall
// @include 	   https://addons.mozilla.org/*/firefox/addon/*
// ==/UserScript==

(function(){

function xpath_get( xpath, node ) {
	//ref: http://subtech.g.hatena.ne.jp/cho45/20071119/1195408940
	node = node || document;
	var result = ( node.ownerDocument || node ).createExpression( xpath,
		function( prefix ) {
			var result = document.createNSResolver( node ).lookupNamespaceURI( prefix );
			if( result )
				return result;
			else
				return ( document.contentType == "application/xhtml+xml" ) ? "http://www.w3.org/1999/xhtml" : "";
		}
	).evaluate( node, XPathResult.ANY_TYPE, null );
	switch ( result.resultType ) {
		case XPathResult.STRING_TYPE : return result.stringValue;
		case XPathResult.NUMBER_TYPE : return result.numberValue;
		case XPathResult.BOOLEAN_TYPE: return result.booleanValue;
		case XPathResult.UNORDERED_NODE_ITERATOR_TYPE: {
			var results = [];
			var item;
			while( item = result.iterateNext(), item )
				results.push( item );
			return results;
		}
	}
	return null;
}

var install_containers = xpath_get( '/descendant::*[local-name() = "div" or local-name() = "DIV"][contains(concat(" ",@class," "), " install-container ")]' )
for( var index = 0; index < install_containers.length; ++index )
	install_containers[index].style.display = "";

})()