Text placeholder on master layout not visible on slides

Hello Storyline developers,

I added a new text placeholder to one of master layouts. The problem is that when I now visit one of the slides in the e-learning, this placeholder is not visible until I reset the slide. My e-learning has +/- 70 slides. Do I really need to reset all those slides one by one or is there an easier solution? Problem with resetting the slides is that all small adjustments also need to be made again.