6.6.0.0. Yes.
To reproduce: Click a drop-down. Do not select an item. Click somewhere in the body. (Drop-down remains) Click the drop-down's down arrow. (Drop-down remains) Click the drop-down's down arrow again. (Finally, the drop-down collapses)
Copy text from the body using Ctrl-C. Paste the text elsewhere in the body using Ctrl-V. The body loses focus.
Pasting markup into the HTML view after initial load works occasionally. Pasting a second time brings up an empty Paste dialog.
It is the minor issues that amplify an end-user's frustration. This damages my product's and my credibility.
Again. I am not a beta tester. I am a paying customer. Get a copy of Chrome and test your Editor.