Animate 包：草稿模式不起作用

Question

我正在将animate软件包与 Beamer 一起使用，并希望使用草稿模式来缩短编译时间。但是，草稿选项似乎会导致编译失败。以下是 MWE：

\documentclass{beamer}
\usepackage[draft]{animate}

\begin{document}
\begin{frame}{Frame title}
    \begin{animateinline}{6}
        \multiframe{41}{i=0+1}{
            frame \i
        }
    \end{animateinline}
\end{frame}
\end{document}

错误出现Missing number, treated as zero在以下\end{frame}行：

./mwe.tex:11: Missing number, treated as zero.
<to be read again> 
                   \setbox 
l.11 \end{frame}

A number should have been here; I inserted `0'.
(If you can't figure out why I needed to see a number,
look up `weird error' in the index to The TeXbook.)

./mwe.tex:11: Illegal unit of measure (pt inserted).
<to be read again> 
                    \setbox 
l.11 \end{frame}

Dimensions can be in units of em, ex, in, pt, pc,
cm, mm, dd, cc, bp, or sp; but yours is a new one!
I'll assume that you meant to say pt, for printer's points.
To recover gracefully from this error, it's best to
delete the erroneous units; e.g., type `2' to delete
two letters. (See Chapter 27 of The TeXbook.)

./mwe.tex:11: Missing { inserted.
<to be read again> 
                   \unitlength 
l.11 \end{frame}

之后又出现了一堆错误。我使用 进行编译，xelatex但使用 时出现同样的错误pdflatex。使用 时也出现同样的错误，\documentclass{article}所以这不是 Beamer 的错。