but I checked and javascript seems to be enabled in my browser.
Edit: Oh. A different post did work. But the original one still doesn't. I assumed it was consistent because it keeps happening for one particular post.
Can you link to the post that was giving you the error?
If it was on every post you tried to agree with, I'd think it was something with your machine/browser. But if it's just giving you an error on that one post, it might be something that needs investigated.
If something on the page slows down the processing of javascript, like a super slow inline image or external avatar, the hijack of the buttons will be delayed. If you click the button before that hijack occurs, you'll see the aforementioned error.
Posts
If it was on every post you tried to agree with, I'd think it was something with your machine/browser. But if it's just giving you an error on that one post, it might be something that needs investigated.
Still won't let me agree. And other posts do let me.