I'm confused to what you guys are seeing on your toolbars. I'm on Firefox and my toolbar works pretty simply. I'm wondering if you got a different download with the newest upgrade?
I just go to my toolbar and click on the thumbs up "I like it!" button on the left. Once I click that, I've stumbled someone, unless a white box comes up that asks you to leave tags, category, and a review. I thought the review box only came up if there was no review (in which it will), but I think it may also come up other times.
Then if you want to Stumble someone without a review, there is a quick option to do so within the upper right of that box. But I really think your doing best by someone to leave tags and a review because I think without proper tagging and review, the Stumble is more likely to just disappear into Cyberspace without being passed along and re-stumbled by others.
I hope some of this helps. I know Stumbleupon is kind of weird to navigate once you are new to it, but once you get it working for you, it is very quick, especially when a review is already left and they don't ask for one.
Maartje, you shouldn't have to copy and paste anything.
Also, I haven't found a way to find any specific person Stumbling. Usually I just get the addresses by asking or sharing on teams like this.