Despite not firing on all cylinders, Thornton battled hard to earn a point from this Premier League game at Paties Road.
It was goal-less at half-time after the home side passed up numerous chances to go ahead but the second-half was in its infancy when Shaun Stevens stole in at the back post to convert Chris Robertson's low cross to make it 1-0.
The Hibs equalised in the 59th minute when, following good work by Andrew Adam, Lea Schiavone calmly picked his spot high in Connar Easton's goal.
The parity lasted eight minutes before substitute, Jordan Hopkinson, ghosted past three visiting defenders then blasted the ball beyond Mark Rowbotham.
When Garry Thomson was brought down in the box in the 77th minute it looked like a penalty every day of the week but the referee, Calum Doyle, thought otherwise to the consternation of the men in purple and white.
Raymond Crichton came close to hitting the goal of the season when he ran from his own half leaving what seemed like more than half of the United team trailing in his wake, however his vicious strike from the edge of the area whizzed narrowly over.
With five minutes remaining, Stuart Drummond played a long ball out of defence. It found debut man, Ryan McEwan, whose pass was perfect for Andrew Adam to run onto and he coolly despatched the ball beyond Easton.
In stoppage time, Hopkinson thought he had snatched a winner for Edinburgh but the referee judged that the ball had gone over the byeline in the build-up and awarded a goal-kick.
Strathore Plant Hire Man of the Match: Daniel McNab
Edinburgh United: Easton, N.Robertson, Grieve, A.Robertson, Nwanze, Bennett, Stevens, Hendrie, Elliot, Auriemma, C.Robertson. Subs: Rutherford, Hopkinson, Fleming, Lee, Cavanagh.
Referee: Mr C. Doyle