Slider fires an event on focus (only on touch on Mobile)

[flecoufle]

What are the steps to reproduce?

create a flow with a slider (output only on release) and a debug node

What happens?

on a mobile browser, a touch gives the focus and then fires 2 events in the debug node a second touch fires only 1 event (it already has the focus)

What do you expect to happen?

on a mobile browser, a touch give the focus and then fires only 1 event (the same behaviour as on desktop browser) (because on a desktop brower, a click on the slider without the focus gives only 1 event)

Please tell us about your environment:

• [x] Node-RED-Dashboard version: 2.26.1
• [x] Node-RED version: 1.2.6
• [x] node.js version: v10.23.0
• [x] npm version: 6.14.8
• [x] Platform/OS: raspbian/PI2
• [x] Browser: Chrome Mobile (Android)

and thanks ! for your great job ;)