I suggest a lighter color for the links in the contextual menu, because I legitimately thought all the links were greyed out, and didn’t even try to click one 
And a double click to rename the column headers would be nice if it doesn’t interfere with anything.
I added two tables on Can I host a Discourse forum for free? (emails and domain services), and I encountered on both the bug which adds empty lines between rows.
But I still couldn’t pinpoint what exactly causes this…
Fixes above mentioned 
UX: Improves context menu text color: