Hi d.gregory.galaxie, yes, unfortunately there is a bug in Firefox 90 with all scaled printing. Whether you change the scale manually (for example, reduce 100% to 70%) or use Fit to page width/Shrink to fit, in either case, content is truncated.

Depending on the page, you could switch to Landscape mode and see whether it will fit without scaling.

A patch has been developed and is in testing in the beta version of Firefox (future Firefox 91). We are hopeful that it will be released as an interim update for Firefox 90, but I don't have information on whether or when that might happen.

Version 90.0.2 was released today to fix this printing problem. https://www.mozilla.org/firefox/90.0.2/releasenotes/