http://coderepos.org/share/changeset/18825

playontumblr.user.js

// ==UserScript==
// @name           play on tumblr
// @namespace      tag:mattn.jp@gmail.com,2008-04-03:/coderepos.org
// @description    play current image or vide on tumblr dashboard with 'ENTER' key. if won't work, pray on tumblr!
// @include        http://www.tumblr.com/dashboard*
// @include        http://www.tumblr.com/show/*
// ==/UserScript==

if (typeof window.Minibuffer != 'undefined') with (window.Minibuffer) {
	var click = function(n) {
		var e = document.createEvent('MouseEvents');
		e.initMouseEvent("click",true,true,unsafeWindow,1,10,50,10,50,0,0,0,0,1,n);
		n.dispatchEvent(e);
	};

	addShortcutkey({
		key: "RET",
		// key: "h",
		description: 'tumblr.play',
		command: function() {
			try { execute( 'tumblr.play', execute('current-node')); } catch (e) { }
		}});

	addShortcutkey({
		key: "h",
		// key: "i",
		description: 'tumblr.reblogcount',
		command: function() {
			try { execute( 'tumblr.reblogcount', execute('current-node')); } catch (e) { }
		}});

	addCommand({
		name: 'tumblr.play',
		command: function(stdin) {
			try {
				if (!stdin.length) stdin = execute('current-node');
				var img = $X('./div[starts-with(@id, "highres_photo")]', stdin[0]);
				for (var n = 0; n < img.length; n++) {
					if (img[n].style.display != 'none') {
						click($X('./a', img[n])[0]);
						return stdin;
					}
					else{
						click($X('./preceding-sibling::a[1]', img[n])[0]);
						return stdin;
					}
				}
				var mov = $X('.//div[contains(@id,"watch_") and .//a]', stdin[0]);
				for (var n = 0; n < mov.length; n++) {
					if (mov[n].style.display != 'none') {
						click($X('.//a', mov[n])[0]);
						return stdin;
					}
				}
			} catch (e) { }
			return stdin;
		}});

	addCommand({
		name: 'tumblr.reblogcount',
		command: function(stdin) {
			try {
				if (!stdin.length) stdin = execute('current-node');
				var count = $X('.//a[contains(concat(" ",@class," "), " reblog_count ")]', stdin[0]);
				for (var n = 0; n < count.length; n++) {
					click(count[n]);
					return stdin;
				}
			} catch (e) { }
			return stdin;
		}});
}