[debug] tracing \patchcmd on input line 5
[debug] analyzing '\document'
[debug] ++ control sequence is defined
[debug] ++ control sequence is a macro
[debug] -- macro cannot be retokenized cleanly
[debug] -> the macro may have been defined under a category
[debug] code regime different from the current one
[debug] -> the replacement text may contain special control
[debug] sequence tokens formed with \csname...\endcsname;
[debug] -> the replacement text may contain carriage return,
[debug] newline, or similar characters