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Now I know what was causing the issue: I had set page zoom to 110% in chrome. At 100% everything works as expected.
Just a guess: maybe it is related to the tooltips The click event might in some browser is captured (and not propagated) by the tooltip instead of the underlying div area.
Same problem here, using Chrome 43.0.2357.130 m on Windows 7. Backlog #139896. Not working is:
- color menu
- more-button in sprint backlog
- expand themes in backlog
I looked for RTEs in the chrome's dev tools, but couldn't find any. The expeted action is simply not carried out.

As Weener described above. Hitting Enter on the first acceptance criteria changes focus to the comment input. It does not generate a second acceptance criteria template. Other browsers work fine. IE does not work, tested it on two machines.
I'm experiencing the same issue in Chrome - the color menu doesn't open reliably. I have to click repeatedly on the CTA until it opens, clicking again on the exact same sport seconds later does not open the menu. It's so frustrating that I've switched to Firefox meanwhile, where it works as expected. Yet, a colleague, who uses Chrome, too, doesn't have this problem. Maybe it is related to a Chrome extension or setting?