S6 Defense mastery glitch/bug

With the release of the new masteries, I decided to re-spec my points in my current pages. Upon trying to re-spec my tank and Darius pages, I found I couldn't pick one of the last tier from the defense ones. I would hover over the perk I wanted, but the description would glitch to the bottom left then back and so forth. This would make it so I couldn't pick one of the last tiers of perks in that tree. It happens every time for me.