Remove trailing whitespace

I have attempted to follow the instructions of a number of posts in this forum that advise using the “Remove trailing whitespace from document” feature of the compile function. They say that it is on the transformations pane of the compile dialogue.
I am using the latest Windows version of Scrivener, but this option does not exist in my compile dialogue.
I’ve also noticed that one or two other options that some people seem to have in this dialogue (such as “Delete struck-through text.”) are also missing.
Why could it be that I do not have the option to Remove trailing whitespace from document?
Thanks, Ian