Diese Karte in einem tschechischen Lehrbuch zeigt Vorarlberg als Teil Deutschlands lol

It also shows the borders in Lake Constance wrong (as in that there are borders).

Brandenburg and Saxony-Anhalt have weird shapes, too.

Bremen and Saarland have open escape routes into their surrounding counties.

Sachsen-Anhalt also got a random chunk of southern Brandenburg there lol and Bremen got skipped completely