Remove slide layout from master not possible in PPT 2019?

Ever wanted to delete a slide layout in the master and come to the conclusion that you can't?

The reason is simple the slide layout is in use in your presentation. You can check this by hovering the mouse pointer over a slide layout, a pop-up will show which slides use the layout. In a brand new presentation you can delete all the slide layouts except for the first one Title slide. That is normal as every new presentation has at least one slide, so the title slide is in use and cannot be deleted.

Below is an example of a custom slide layout displaying the pop-up.

So if you want to delete the slide layout the option is greyed out.

You can also check in the presentation. If you click the Layout button on the Home tab you will see which layout has been applied to the slide. In our example slides 7-10).

To remove the slide layout you will have to apply another layout to the four slides. This will have implications, for example the arrow on the slides will disappear. The centered text will be aligned to the left. So select the slides and apply the new layout, here I have applied the Empty layout.

Now you can delete the slide layout in the master.