Eggcorns (Wikipedia / YouTube video by RobWords) are language mistakes that sometimes take over and change the spelling and perhaps even the meaning of a word. This is rare in German because there’s fewer homophones but in this episode of Wort der Woche, DW explains how “munttot” became “mundtot”. Available as audio or transcript.
The German Wikipedia page needs some improvement, though.
Only contains deliberate wordplays and somewhat cringy dad jokes as examples…