GoBDokumente is a macOS application Since Apple broke the Safari user agent string

Mozilla/5.0 AppleWebKit/537.36 (KHTML, like Gecko; compatible; ClaudeBot/1.0; +claudebot@anthropic.com)

under macOS Big Sur, the automatic detection of which version of GoBDokumente you need to download is temporarily suspended and you have to manually choose which version you want/need to download:

Download Version 1 for macOS 10.11 - 10.15
Download Version 1.8.2 for macOS 11+
Download Version 2 for macOS 11.0+ (incl. support for M1)