Not 10 years, but yeah, German was completely reformed some 24 years ago. It is still pretty major as several countries (Germany, Austria, Switzerland and others with german-speaking minorities) had to coordinate and consent.

See https://en.wikipedia.org/wiki/German_orthography_reform_of_1...

I as a child started learning the old orthography in school, was taught the "new" one later on and had to use it and even the "new new" one (there was basically a version 2.1 minor update). To this day I am confused about how to correctly spell and write words, and I always end up mixing old/new orthography. The fact that almost all major newspapers refuse to fully adhere to the new orthography and use custom deviations every here and there does not exactly help.

Lessons learned: It is a mess, don't do it.