gin-gonic Redirecting HTML following of POST, from Javascript XMLHttpRequest

I am trying to build login pages with Gin-gonic, but I got trouble in redirecting browser.

> main.go
>
>go
> router.GET("/login", getLoginPage)
> router.POST("/login", authentication.Login)
> router.GET("/dashboard", showMainPage)
>

If user press the button in html

> login.html
>
> html
> <input a href="javascript:void(0);" class="btn btn-primary btn-user btn-block" id="loginButton" value="Login"></input>
>

Then, Javascript function will be working. The reason why I coded like this is that, I learned that UserID and Password should be hashed before sending to server. (Due to some sort of security problems like tapping, as far as I know)

> login.js
>
> js
> document.getElementById("loginButton").addEventListener("click", tryLogin, false);
> // Get user inputs like ID and PW
> var request = new XMLHttpRequest();
> request.open("POST", "/login");
> request.send(formData);
>

And now, router.POST("/login", authentication.Login) will work.

> auth.go
>
> go
> func Login(c *gin.Context) {
> id := c.PostForm("id")
> pw := c.PostForm("pw")
>
> // Hash password again, Check Validation and Find user in database
>
> // If all inputs are correct, Logged in.
> c.Header("Content-Type", "text/html")
> c.HTML(http.StatusOK, "dashboard.html", gin.H{
> "title": "title of my page",
> "username": "I want to send some data like this",
> "usernickname": "TyeolRik",
> }) // But the thing is c.HTML not directing as I want. but it returns well checked in Postman.
> }
>

But c.HTML doesn't showing rendered HTML screen in browser (Chrome and Edge checked) and also, c.Redirect() doesn't work neither.

> auth.go
>
> go
> func Login(c *gin.Context) {
> id := c.PostForm("id")
> pw := c.PostForm("pw")
> // Hash password again, Check Validation and Find user in database
> c.Redirect(http.StatusMovedPermanently, "/dashboard")
> }
>

How can I redirect HTML easily? I temporarily used window.location.href = '/dashboard'; in Javascript. But It cannot be rendered like using gin.H{something}

Is there any tips for me?

Thanks to @mkopriva, I found out that XMLHttpRequest() in javascript doesn't work with *gin.Context.HTML() of gin.gonic

Browser doesn't redirect with XMLHttpRequest() as server returns.

Final code (works well)

login.js

function tryLogin() {
    const email = document.getElementById("loginFormEmail").value;
    const pw = document.getElementById("loginFormPassword").value;
    var hashedPW = sha3_512(pw);

    var hashedForm = document.createElement("form");
    hashedForm.setAttribute("charset", "UTF-8");
    hashedForm.setAttribute("Content-Type", "multipart/form-data");
    hashedForm.setAttribute("method", "POST");  // Post
    hashedForm.setAttribute("action", "/login"); // URL destination

    var hiddenField = document.createElement("input");
    hiddenField.setAttribute("type", "hidden");
    hiddenField.setAttribute("name", "email");
    hiddenField.setAttribute("value", email);
    hashedForm.appendChild(hiddenField);

    hiddenField = document.createElement("input");
    hiddenField.setAttribute("type", "hidden");
    hiddenField.setAttribute("name", "password");
    hiddenField.setAttribute("value", hashedPW);
    hashedForm.appendChild(hiddenField);

    document.body.appendChild(hashedForm);
    hashedForm.submit();
}

When server validate POST-ed login, then

auth.go

// Some validation
// If ID and PW is right,
c.Redirect(http.StatusMovedPermanently, "/dashboard")

This works.