Hi Derek,
Different browsers will render text slightly differently. Even if the difference is very small on average, these differences can sometimes result in a word wrapping onto a new line in one browser but not in another. This is what seems to be happening in your screen shot (the word "frequently" is appearing on a different line in publish mode).
In general, we recommend that you add a little extra space below a block of text so if text extends to a new line it won't overlap another object.
If you can't do this, there is a property,
Text Rendering, which allows you to select
WYSIWYG (what you see is what you get). WYSIWYG rendering gives a consistent spacing/placement across all browsers / devices, but it does make authoring and viewing a little slower (it's more computationally intensive). It's also slightly less crisp, so we don't recommend using it for all text in your lesson.