Steps to reproduce: 1. emacs -Q 2. load org 9.0.4 3. (add-to-list 'org-latex-packages-alist '("" "polyglossia" nil)) 4. switch to org-mode and attempt to render any fragment, e.g. $test$ 5. error
If you look at the tex file produced, polyglossia has been included in the preamble even though snippet-flag is nil. Additionally longtable, wrapfig, rotating, capt-of, hyperref are all included in the preamble despite the fact their snippet-flag is nil. (These are packages in org-latex-default-packages-alist). The relevant function that has been changed in 9.0.4 is `org-create-formula-image'. It looks like the function used to generate latex-header, `org-create-formula--latex-header', has been replaced with `org-latex-make-preamble' (defined in ox-latex.el). Restoring org-create-formula--latex-header from 9.0.3 and redefining org-create-formula-image again restores the old behaviour for me. Of course I don’t know what the problem actually is with the new function. I should say I am not sure if this problem is specific to my environment. Please let me know if you can reproduce it. Emacs : GNU Emacs 25.1.1 (x86_64-unknown-cygwin) of 2016-09-17 Package: Org mode version 9.0.4 (9.0.4-elpa @ /cygdrive/c/home/.emacs.d/elpa/org-20170124/)