Clutch pedal remains down

Moin, today at a longer exit the clutch pedal just stayed down. It can be pulled up manually again and then stays there, but the function is almost at zero. I then had a rather interesting drive home in the 2nd gear, with every stop engine out and gear out, stop, gear back in and start with the starter and roll up. The whole with warning turn signal and about 40 things among others also on the east Westphalian road. I took a picture under the A-board, this white rod with the yellow edge moves in front and back, there seems to be mechanically everything in order. The cuff is a little oil-moist. The whole thing happened suddenly without warning. Has anyone ever had this before? Greetings Micha (850, year 05/95, M56)