Text Framing is a text property which allows framing to be applied to dis-contiguous text ranges, while remaining a single frame for the full extent of the text that has the same frame attributes.
Prior to QuarkXPress 2017, such effect were extremely difficult to achieve automatically, and the available solutions were limited, as well as quite complex to implement.
The various Line Options correspond to the text background frame part of the Tools Bar of the QuarkXPress user interface (note that Text Framing is a text attribute and therefore can be combined with any of the other text attributes, including text background shade and text stroking).
The Background Frame, when specified in macro options, text formatting attributes and saras, works exactly as it does in QuarkXPress. That is to say, the frame extends by a fixed amount from the edge of the text, meaning that the frame "width" depends on the width of the text being shaded, as shown to the left, below.
On the left: Background Frame, when in QuarkXPress, Macro Options, Text Formatting Attributes and SARAs. On the right: Background Frame with fixed sizes as available in Minicalendar options.
*In minicalendar options, it is possible to produce frames of the same position and size regardless of the text/number to which it is applied, as shown above, to the right.