1) I see the font used for class .query-history .entry is monospace, shouldn't it be Helvetica as per style guide ? the font for Messages > text is also monospace.
As per Dave's comment, we have added this to the styleguide backlog. We will be adding monospace entries to the styleguide.
2) Can 1px top border be added above first entry in left panel to differentiate from above panels ?
We have updated the patch to include a 1px solid #cccccc border at the top.
3) No query execution message appears if i run same query second time, please refer screenshot.