blur

**I'm submitting a bug report**

**Please tell us about your environment:**
* **Operating System:**
Windows 10

* **Node Version:**
68.11.3

* **NPM Version:**
6.6.0

* **Browser:**
Firefox 64.02

* **Language:**
ESNext

**Current behavior:**

Create a value converter 👍
```
export class AddStringValueConverter {
toView(value, string) {
let s = ""+value+string;
console.log("add-string :",value+"=>"+""+s);
return s;
}
}
```
Create a template 👍
```

```

now input "2" un first field, then puche "tab" (it display "2.00")
then push "Shift+Tab", input "2"
then it display "2" and not "2.00" !!

* **What is the expected behavior?**
showing "2.00" and not "2"

Reproduce the value converter and input template in Firefox using the `blur` update trigger, then compare the first tab and Shift+Tab flows. Trace the binding behavior around focus changes; done means both interactions display the converted value with `.00`.

Written by the indexing model from the issue text.