Your bug report

#69404: Loss of latex-mode fontification when loading libraries in latex-mode-hook that require json-mode

which was filed against the emacs package, has been closed.

The explanation is attached below, along with your original report.
If you require more details, please reply to 69404@debbugs.gnu.org.

-- 
69404: https://debbugs.gnu.org/cgi/bugreport.cgi?bug=69404
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