Well that's a new one :)

Strictly-speaking it's not, it's been happening for...about 4 months now. But, you know those costs that are so minor the cost of writing out a report is a bigger pain? And the first cost keeps repeating until it's exceeded the second? That. Sorry ;p.

(In reply to comment #0)

Windows 7/Ubuntu 12.4 on the latest Firefox release. Screenshot attached.

What's "latest"? And any output in the JavaScript error console?

21.0, and Firebug shows nada on the JS front.

Appears fine for me on FF 21.0.1 + Win7

Oliver are you using any suspicious addons?

Addblock, cryptocat, HTTPSeverywhere, a dictionary and some things that obliterate google and facebook tracking cookies. So, no. Does it appear fine for you consistently, or on one page?

It appears fine for me all the time. I tried it on my local wiki as well as on en.wp

I suggest putting a testme keyword and UNCONFIRMED

What skin?

(Now tried with all plugins disabled. Bupkis.)

I can reproduce this with Firefox 18 on Linux.
Did not manage to reproduce with Opera 12.14.

I am logged in and I go to http://en.wikipedia.org/wiki/Special:NewPagesFeed and open a bunch of items (not the "Review" button, but going to the article itself).

Using "Inspect Element" in Firefox and clicking "Style", the PageCuration toolbars correctly aligned to the right have

element {
    right: 0px;
    left: auto;
}

while those aligned to the left have an additional

position: relative;

in that "element" CSS definition.

working version and skin

I am using the default Vector skin. I have added a screenshot.

Attached:

Try Monobook, see what happens?

Same thing.

Then...that's just weird, at one of our ends :P

bsitu wrote:

I tried it on different machines/browsers via browserstack, but I couldn't reproduce this weird bug

I can still reproduce this with Firefox 23 on Fedora 19 (but ont after reloading the page). So if there is any more info that I could gather, tell me how. :)

Tom Morris hypothesises that it appears if the page has left-aligned elements.

This is one of those hairy bugs that could use some additional QA investigation, so CCing Chris.