I have also experienced the offered lesson order changing upon refresh.
I’m currently on someone else’s computer. So no scripts, or even Tampermonkey on this one. I checked, and the lessons in my queue were completely the same between refreshes. I jumped onto my phone and started the lessons there - they were still in the exact same order as when I started lessons on this “clean” computer.
So you may be right that one or more scripts interfere with this.
Maybe that’s why I sometimes have a lesson where they refer to a word that they claim I learned during that level, but without me having actually learned that word yet.