Bulk download the videos using a tool like the 'DownThemAll' plugin for Chrome, then run them in VLC.

Unfortunately, there's no way to make the button default to queue, it's limited to these options.

However, I modified the tumblr bookmarklet to open the share form in a new tab. It's normally set to "Post", but clicking the bookmarklet again changes it to "Queue".

javascript:(function()%7Bvar%20d%20%3D%20document%2Cw%20%3D%20window%2Ce%20%3D%20w.getSelection%2Ck%20%3D%20d.getSelection%2Cx%20%3D%20d.selection%2Cs%20%3D%20(e%20%3F%20e()%20%3A%20(k)%20%3F%20k()%20%3A%20(x%20%3F%20x.createRange().text%20%3A%200))%2Cf%20%3D%20'https%3A%2F%2Fwww.tumblr.com%2Fwidgets%2Fshare%2Ftool'%2Cl%20%3D%20d.location%2Ce%20%3D%20encodeURIComponent%2Cp%20%3D%20'%3Furl%3D'%20%2B%20e(l.href)%20%2B%20'%26title%3D'%20%2B%20e(d.title)%20%2B%20'%26selection%3D'%20%2B%20e(s)%20%2B%20'%26shareSource%3Dbookmarklet'%2Cu%20%3D%20f%20%2B%20p%2Csw%20%3D%200%2Csd%3Bif(!%2F%5E.%2Btumblr%5C.com%5C%2Fwidgets%5C%2Fshare%5C%2Ftool%5C%3F%2F.test(l.href))%7Btry%7Bsd%20%3D%20d.createElement('div')%3Bsd.style.height%20%3D%20'100px'%3Bsd.style.width%20%3D%20'100px'%3Bsd.style.overflow%20%3D%20'scroll'%3Bd.body.appendChild(sd)%3Bsw%20%3D%20sd.offsetWidth%20-%20sd.clientWidth%3Bd.body.removeChild(sd)%3B%7Dcatch(z)%7B%7D%3Btry%7Bif(!%2F%5E(.%5C.)%3Ftumblr%5B%5E.%5D%24%2F.test(l.host))%20throw(0)%3Btstbklt()%3B%7Dcatch(z)%7Ba%20%3D%20function()%7Bl.href%20%3D%20u%3B%7D%3BsetTimeout(a%2C%2010)%3B%7D%7Delse%7Bdocument.getElementsByClassName('dropdown-area%20icon_arrow_carrot_down')%5B0%5D.click()%3BjQuery('.item-option%3Acontains(Add%20to%20queue)').click()%3B%7D%7D)()

To use it, click the bookmarklet once to open the tumblr share tab and again to set the post type to queue.

YouTube Thumbnail Image Search Bookmarklet

Opens a new tab with Google Image Search results for the video's cover image.

javascript: (function () { var t = document.querySelector("link[itemprop='thumbnailUrl']").href; m = "https://images.google.com/searchbyimage?site=search&image_url=" + t; w = window.open(m, "addwindow"); setTimeout(function () { w.focus() }, 250) })()

Tested your bookmark now. A pity that won't work anymore. I can't offer you a solution to Chrome blocking window.open, but have you considered the alternative: Just make a search shortcut in Chrome, that looks something like this: https://pinboard.in/search/u:myname?query=%s and assign it to a key, like p. Then all you have to do is Cmd T + p <your query>.