In our latest pdfHTML release we've fixed a margin processing bug that was affecting checkbox rendering.

In versions 4.0.1 and lower, checkboxes with {{width: 100%}} and {{display: block}} CSS properties could be rendered incorrectly. This was due to the margin erroneously being applied twice in certain situations. 

Below is an example of HTML that could trigger this bug: 

checkbox example 
<!DOCTYPE html>
<html>
<head>
<style>
    input[type="radio"], input[type="checkbox"] {
        margin: 1px;
    }

    .form-control {
        width: 100%;
        display: block;
    }
</style>
    <title>checkbox example</title>
</head>
<body>
<table style="border-width: 0px; padding: 0px; margin: 0px; border-spacing: 0px;">
    <tr>
        <td style="background-color: red; border-width: 0px;  padding: 0px; margin: 0px;">
            <input type="checkbox" class="form-control" value="true"/>
        </td>
    </tr>
</table>
</body>
</html>


The bug would result in the checkbox to be rendered as shown here:

In pdfHTML release 4.0.2 we have addressed the margin issue, and the checkbox will now properly be rendered as shown below:

Since this is a bugfix, any changes are applied in the back-end. Therefore, there should be no changes required in how users currently process HTML.