I've noticed that, when using the schematic editor for recent answers, the "Save and Insert" button saves the schematic but does not close the editor and return to the answer edit box.
I can click the "X" close button to return to the answer edit box and see the code inserted for the schematic image.
However, the preview pane does not show the image nor does the preview pane update from that point on in the editing session.
If I save the answer, the schematic image shows up however, if I then attempt to edit the answer, the tool bar is missing and the preview pane is empty.
I tried closing my browser session and restarting without any change. I tried another browser entirely without any change.
Here's the answer I worked with this morning: https://electronics.stackexchange.com/a/129417/10475
I tried deleting the schematic insertion code and saving the answer. When I reopened for edit, the tool bar was present and the preview worked.
So, evidently, the schematic insertion code inserted by schematic editor has a problem. Has anyone else noticed this?