I've no idea since when my Firefox doesn't show highlighted code fences on any web pages. Specifically it happens inside the <textarea> tags. Anyone with an idea of the possible reasons? I've tried to disable the add-ons one by one and inspect, nothing ever changed even when I disabled all my add-ons and meanwhile I refresh the page every time I disabled an add-on. I added a few screenshots for comparison. Any help or tips are appreciated! Big Thanks!