diff --git a/ui/src/components/slider/slider-utils.js b/ui/src/components/slider/slider-utils.js
index 8d50b8958c2..801e521c564 100644
--- a/ui/src/components/slider/slider-utils.js
+++ b/ui/src/components/slider/slider-utils.js
@@ -168,7 +168,9 @@ export let SliderMixin = {
       }
       else if (event.isFirst) {
         this.dragging = this.__getDragging(event.evt)
+        console.log('started')
         this.__updatePosition(event.evt)
+        this.__updateValue()
         this.active = true
       }
       else {
diff --git a/ui/src/directives/TouchPan.js b/ui/src/directives/TouchPan.js
index 1b9ad1e79f1..586042584b8 100644
--- a/ui/src/directives/TouchPan.js
+++ b/ui/src/directives/TouchPan.js
@@ -220,9 +220,13 @@ export default {
           lastX: pos.left,
           lastY: pos.top
         }
+
+        if (detected === true) {
+          ctx.move(evt, true)
+        }
       },
 
-      move (evt) {
+      move (evt, startEvent) {
         if (ctx.event === void 0) {
           return
         }
@@ -238,7 +242,9 @@ export default {
             }
             else {
               if (ctx.event.isFirst === true) {
-                handleEvent(evt, ctx.event.mouse)
+                // mouse listener is passive, so avoid handling start event
+                startEvent !== true && handleEvent(evt, ctx.event.mouse)
+
                 document.documentElement.style.cursor = 'grabbing'
                 ctx.event.mouse === true && document.body.classList.add('no-pointer-events')
                 document.body.classList.add('non-selectable')