async def METHOD_NAME(ns: BufNamespace, win: Window, buf: Buffer) -> AsyncIterator[ExtMark]:
    cursor = await win.get_cursor()
    for idx, mark in enumerate(await _ls_marks(ns=ns, buf=buf)):
        if not idx and mark.begin == cursor and mark.end == cursor:
            await _del_marks(buf=buf, ns=ns, marks=(mark,))
        else:
            yield mark