A family of Microsoft presentation graphics products that offer tools for creating presentations and adding graphic effects like multimedia objects and special effects with text.
It turns out that this is deliberate, not a bug. It's an accessibility feature that makes it easier to click the correct button.
I've already used Feedback to ask that they make this an OPTIONAL feature; either a default that we can turn off or a feature that people can enable if/when they need it.
This would be a very good time for anyone else who's annoyed by this to send Feedback also.. The more the merrier (and the louder our voices).