src/Pure/PIDE/document.ML

                 let
                   fun init () = init_theory deps name node;
                 in
                   (singleton o Future.forks)
                     {name = "Document.edit", group = NONE,
-                      deps = map (Future.task_of o #2) deps, pri = 2, interrupts = false}
+                      deps = map (Future.task_of o #2) deps, pri = 0, interrupts = false}
                     (fn () =>
                       let
                         val prev_exec =
                           (case prev of
                             NONE => no_id