The width of the following form is not constrained properly when using Firefox. Instead it spans the whole screen although in Chrome it does not.

<form class="form-horizontal" role="form">
    <legend class="righter">Legend</legend>
    <div class="form-group">
        <label for="title" class="col-lg-2 control-label">Title</label>
        <div class="col-lg-4">
            <input type="text" class="form-control" id="title" placeholder="..." />
        </div>
    </div>
    <div class="form-group">
        <label for="id" class="col-lg-2 control-label">UUID</label>
        <div class="col-lg-4">
            <input type="text" class="form-control" id="description" placeholder="..."/>
        </div>
    </div>
</form>

In JSFiddle it behaves similarly to Firefox: http://jsfiddle.net/dy5KP/1/

How can I make it look like in the following picture (except for the marks) and diminish the width of the inputs?

Bootstrap Grid

At some point the BootStrap Grid System will try to collapse the fields.

There are four grid classes:

• col-xs-* : Mobile, never stacks
• col-sm-* : Tablet, stacks below 768 px
• col-md-* : Laptops, stacks below 992 px
• col-lg-* : Desktop, stacks below 1200 px

Part of the problem when looking at the code in jsFiddle is you have less real estate to look at. When I open your code in firefox and append /show to the fiddle name, I am able to get the proper behavior by making the screen wider than 1200 pixels. See bottom of post for images

Solution

One solution would just be to narrow the breaking point by choosing a smaller grid column from the list above.

<!-- language: lang-html -->

<div class="form-group">
    <label for="title" class="col-xs-2 control-label">Title</label>
    <div class="col-xs-4">
        <input type="text" class="form-control" id="title" placeholder="..." />
    </div>
</div>

Here's a fiddle: jsFiddle

Which will look like this at any screen width:

For more info you can look at Horizontal Forms on the Bootstrap CSS page.

Breakpoint Demo

Here's proof that your demo is working correctly by breaking at 1200px:

1199px:

1200px: