You can test this yourself by installing consult, turning on vertico-posframe-mode, then issuing M-x consult-buffer. At the prompt, type b SPC to attempt to narrow to the buffer list, causing the error.
This works correctly with plain vertico, it is only vertico-posframe that fails.
When using consult in conjunction with vertico-posframe, attempting to narrow a buffer throws an error:
You can test this yourself by installing consult, turning on vertico-posframe-mode, then issuing
M-x consult-buffer
. At the prompt, typeb SPC
to attempt to narrow to the buffer list, causing the error.This works correctly with plain vertico, it is only vertico-posframe that fails.
The full backtrace: