Well this is strange.

I tried cleaning the cache again (tried it before) and it's still the same.

I even tried it in chromium and i have exactly the same problem there.

Then i tried a different firefox profile and it works correctly there.... i have no idea what going on.

edit: Well, i deleted the cache in the new firefox just for fun and now i get the same wrong behavior there. So it's reproducible in all my browsers.

I noticed some css rules are not applied in the browsers where it does not work:

These are missing:

.iFrame .snapTypeList li label input[type="radio"] + .radio-helper { height: 36px; line-height: 36px; padding: 0px 14px; display: block; background: #EEE none repeat scroll 0% 0%; color: #000; border-radius: 4px; }

.iFrame .snapTypeList li label { cursor: pointer; }

They are located in: style_popup.css

I then noticed that in the browsers where it does not work a different style_popup.css is loaded. It has 974 rules there, while the version that works has 993 rules.

As i said, i deleted the caches in firefox and chromium multiple times (+ restart). I have never seen something like this before. :) Maybe you have an idea what's going on?

Tested in Firefox 39 and chromium Version 44.0.2403.107 (64-bit) both on linux.