Bolding text UI inconsistency in new Marketo email builder

I’m not sure if this is a bug, an oversight, or intentional, but the UI in the new email builder for text styling isn’t the most intuitive. Right now, bolding (italicizing, etc) specific words from this black bar menu works as expected:

However, when you bold from the right sidebar, it bolds the entire text block:

It would be great if both of these text styling options functioned the same. Thank you! 😊