As discussed in the forum posts below, there is a bug numerous people are experiencing printing US Letter-size Writer documents on MacOS. Changing the dimensions to 8.5x10.99 or the like fixes the problem (but it is rather frustrating until you find that fix which is not necessarily intuitive). It appears to happen on both 5.3.7 and 5.4.2 at least.
Steps to Reproduce:
1. Create new document or open an existing one that is Letter page size.
2. Put some text in it
3. Select print from the menu and the preview image will show the problem.
Text is oriented at a 90 degree angle (off to its side) and cut off.
User Profile Reset: No
User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.13; rv:57.0) Gecko/20100101 Firefox/57.0
Created attachment 137989 [details]
Screenshot of problem
See attached screenshot
The problem appears to be Mac-specific. The same file on Ubuntu 16.04 behaves correctly.
*** This bug has been marked as a duplicate of bug 92190 ***