I clicked on "Analyze Game" and Stockfish wouldn't find any blunder or mistake. I had lost two matches against the opponent previously (on other days) so this game was just ... perfect.
(Is there any blog posts / etc on the distribution of accuracy-percentages, potentially for various ELO levels? I am pretty surprised that I played so accuracte given that I tend to blunder regularly)
They played at 82%, one blunder, 2 mistakes, 1 imprecision (sry, translating terms to english on the fly). So I don't think they were playing extremey bad.
Imprecisions are called inaccuracies, rest is correct.