[texhax] Compatibility problem with newtxtext package

[Bob Tennent]

 >|So after paring everything extraneous away into a 8-line
 >|MWE that is text-only (no math symbols), the culprit
 >|appears to be some kind of change in the newtxtext
 >|package, presumably with respect to font metrics, between
 >|2014 and 2017, though I can't be completely sure.
 >|Possibly in interaction with LaTeX's \large or \emph{}
 >|macros.

If I typeset your MWE using txfonts rather than newtxtext,
it fits on two lines. 
 
 >|I would like my 8 pages back on my upgraded system, at
 >|least for this one document. Suggestions on what to do?

The newtx packages have been evolving and it is explicitly
stated that this is to "improve" metrics. You shouldn't
expect compatibility in these circumstances. Since version
1.4, txfonts aren't even used in newtxtext.

You could see if something like scaled=0.995 helps.

Bob T.