Annoying Text Focus Space + Delete Bug

Wondering if anyone else is experiencing this, or has suggestions of things I can try to further isolate the issue. This started a few days ago, so it may be related to the Mac 10.9.2 update. Here's what I submitted to the bugbase. But instead of reading, just check out the video to see the problem.

When focus is shifted away from one panel, like the stage, and then back again, Flash acts as if the spacebar has been pressed, followed immediately by the delete key. This is easy to demonstrate on the stage. I have posted a video to http://youtu.be/jArDPmJ8tOQ

It also happens in other panels, such as if you select the font name in the text properties panel.

If text is selected, then the text is deleted by this space + delete action. So changing font properties is very difficult because selecting text and then using the text properties panel will result in the text being deleted.

Interestingly, the space + delete is recorded in the Undo stack, as you can then use Command+z to get the text back. If you try to use Edit, Undo then the text will return but the space + delete happens again and deletes it. Command+z does not change the focus so it works to save the text.

This does not occur in other apps such as web browsers, Mail, Pages, TextEdit, etc. It does happen in Photoshop CC, so it might be a bug in some shared code there. It does not happen in Illustrator CC. It does not happen in Flash CS6. It may have to do with the Apple 10.9.2 update as the problem started at about the same time. It happens consistently, 100% of the time on my Mac Pro, but not on my MacBook Air.

I have eliminated the possibility of system extensions and accessibility options.

Steps to reproduce bug:

1. Create a new Flash movie and put a text field on the stage.

2. Select the text.

3. Select a menu in the menu bar, just the menu, not an item in it.

4. Click on the menu again to dismiss it without using a menu item.

5. Focus returns to the stage and the space + delete occurs about a half a second later.

See the video for an example and more details.