(tested in chrome)
Bug A.
1. Edit a json
2. Note the cursor is at the top left of the document, but it's grayed, because the focus isn't there
3. Hit ctrl+A. It doesn't work right, because the focus was elsewhere
so, I tried it this way.....
Bug B.
1. Edit a json with a short amount (several lines)
2. Drag from the bottom right of the json window toward the top left (the goal being to select all the text). Don't let go of the mouse button yet.
3. Actually, you should drag beyond the top left of the popup window, into the the page behind the popup window. The point is to whip your mouse up without paying close attention to where you stop.
4. Release the mouse button
5. The popup disappears!
Expected: the popup does not disappear.