Operation tooltips now disappear if you hover over them while dragging an opertion.

src/web/OperationsWaiter.js

@@ -167,7 +167,8 @@ OperationsWaiter.prototype.opListCreate = function(e) {
 OperationsWaiter.prototype.enableOpsListPopovers = function(el) {
     $(el).find("[data-toggle=popover]").addBack("[data-toggle=popover]")
         .popover({trigger: "manual"})
-        .on("mouseenter", function() {
+        .on("mouseenter", function(e) {
+            if (e.buttons > 0) return; // Mouse button held down - likely dragging an opertion
             const _this = this;
             $(this).popover("show");
             $(".popover").on("mouseleave", function () {
@@ -178,7 +179,7 @@ OperationsWaiter.prototype.enableOpsListPopovers = function(el) {
             setTimeout(function() {
                 // Determine if the popover associated with this element is being hovered over
                 if ($(_this).data("bs.popover") &&
-                    !$(_this).data("bs.popover").$tip.is(":hover")) {
+                    ($(_this).data("bs.popover").$tip && !$(_this).data("bs.popover").$tip.is(":hover"))) {
                     $(_this).popover("hide");
                 }
             }, 50);