Affinity Publisher newbie here. After working in Publisher with an image that had changed from "image" to "pixel", I found I was no longer able to draw a thin rule around it in the way it can be done with a text frame or image frame. There's always the Outline layer effect, but it does the job only partway. With Outline there don't seem to be controls for how the corners are drawn—they are always rounded. But is there a way to alter the corners using some other controls in the program?