How can I get rid of the selection handles for my marks in PrizmDoc Viewer?

I would like to remove the mark selection handles from the marks (annotations and redactions) in the viewer so that my users can't resize marks, but so they can still move the marks around. How can I do this?

The easiest way to achieve the functionality you're looking for would be to simply change the CSS for the mark handles to set their display to none !important. The CSS for the mark handles can be found in viewercontrol.css. See the following code for an example:

/* mark selection handles */
.pccMarkHandleTopLeft,
.pccMarkHandleTopCenter,
.pccMarkHandleTopRight,
.pccMarkHandleMidLeft,
.pccMarkHandleMidRight,
.pccMarkHandleBottomLeft,
.pccMarkHandleBottomCenter,
.pccMarkHandleBottomRight,
.pccMarkHandlePoint,
.pccMarkHandleTextSelectionStart,
.pccMarkHandleTextSelectionEnd {
    position: absolute;
    width: 40px;
    height: 40px;
    display: none !important;
    background-image: url(data:image/png;base64,iVBORw...);
}

@media screen and (-webkit-min-device-pixel-ratio: 2), 
       screen and (min-resolution: 2dppx),
       screen and (min-resolution: 192dpi) {
    .pccMarkHandleTopLeft, 
    .pccMarkHandleTopCenter, 
    .pccMarkHandleTopRight, 
    .pccMarkHandleMidLeft, 
    .pccMarkHandleMidRight, 
    .pccMarkHandleBottomLeft, 
    .pccMarkHandleBottomCenter, 
    .pccMarkHandleBottomRight, 
    .pccMarkHandlePoint, 
    .pccMarkHandleTextSelectionStart, 
    .pccMarkHandleTextSelectionEnd {
        -webkit-background-size: 40px 40px;
                background-size: 40px;
        display: none !important;
        background-image: url(data:image/png;base64,iVBORw...);
    }
}

You will want to set the !important flag so that the functions inside viewercontrol don't set the display back to block.

One thing you may want to do is separate out pccMarkHandleTextSelectionStart and pccMarkHandleTextSelectionEnd to not include display: none. This way, the text selection annotations are able to be edited, since they are reliant on the handles for "movement" because they select a portion of the text signified by the handles.