> By the way: no-init-from-resources is a global variable set by Emacs
> during startup if (and only if) "-Q" is given, thus X resources should
> not be applied.

I built fine with the
0001-lisp-faces.el-Fix-application-of-X-resource-attribut.patch .

  ./src/emacs -Q -r

works as expected. However, commenting out my entire init.el,

  ./src/emacs -r

still starts Emacs with a white background, contrary to expectation.
So the patch doesn't fix 16434.