Is it my imagination, or does that look like a blue inline crimp terminal on the left ? Incredibly badly crimped (used side cutters) at that so no wonder wire fell out - it'll be loose and a fire hazard.
It's your imagination - it's blue sticky tape, and by the looks of it the f***wit who put it on didn't even twist the ends of the conductors together first.
It's definately a thru crimp and fitted completely inappropriately. That'll be where and why the lights have failed. And can you please stop littering this forum with your foul language?
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