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Restores normal thumbnails size
DEPRECATED: This script will not be updated in the future and may break (and if it does, it won't be fixed). I suspect that YouTube is trying to A/B test their new layout on us which means that rewriting this script completely may break it for users with older layout. Try YouTube Smaller Thumbnails instead if this script fails.
Restores normal YouTube thumbnails. This script will take current thumbnails number and increase it by 1. Old markup almost always had one more thumbnail.