When you select one of these placeholders:

Safari & Firefox render the cursor after the placeholder (desired)
Chrome renders the cursor before the placeholder

However, ultimately, editor developer will search for a solution,
where placeholders "just work" in all situations. E.g. for elements with centered text.
This currently only works when the <br/> element is removed as soon as a field is focused.
See also: https://github.com/michael/web-editing/issues/5

When the br is removed, Safari/Chrome render this correctly,
but in Firefox the cursor is always rendered at the very beginning, ignoring the centering.