saveAs saves only last saveAs request, used to be able to save multiple files, Firefox

A JavaScript in an html file run from the desktop used to be able to save multiple text files from multiple saveAs calls that look similar to this:

var text = simplekey + "\r\n\r\nReference answer key string:\r\n" + refanswerkey;
var filename = basefile+"_SimpleKey"; if ( versions.length > 1 ) { filename += "s" }
var blob = new Blob([text],{type: "text/plain;charset=utf-8"});
saveAs(blob, filename+".txt");

But now just today (2-5-2019), even using the same html files as before, only the last saveAs request actually works. No errors are generated by the other requests, just no files are generated. If I comment out the last saveAs, then the second-last request produces a file. Firefox v65.0.