Well, this time the lens didn’t pop off. What happened here is that the black plastic tab broke that the corner light retainer spring attaches to. With no retainer the light assembly popped out and rattled around on the fender and broke the lens.
No way I am going to replace this whole black plastic shroud around the headlights so I needed to fix it. Really we need almost anything for the retainer spring to hook on to so I drove a self-tapping screw with a large head into the plastic near the broken spot.
Now I could simply hook the retainer spring over the screw and it stays put. Of course we had to buy a new lamp assembly to replace the broken one.
No cost but for a screw I had laying around.