Thank you all for your great hints.
@quantumf: Yeah, you're right. On

I thought for a while, coming to the conclusion, that I have much more liberties for the ko in the corner, so it's good to save these stones. Getting out, of course, is better and deals with his moyo on the bottom side I furiously invaded later.
@entropi: Nice sequence you presented. In the game I didn't see, that this is the L-group. Actually, I know there exists something called "the L-group", but I don't care...
In the game I read out that White is dead (except for an very unfavorable ko) and missed your line.
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