Rmarkdown和pandoc-2.5和2.6的新错误（无法解码byte \ xa9）

Question

我最近上传了一个新版本的R软件包，其中R markdown小插图在我的Ubuntu系统上使用pandoc 2.2运行良好。

今天我通知R CRAN检查以下内容

This version fails on both Fedora Linux and macOS with pandoc 2.5

--- re-building ‘Rmarkdown.Rmd’ using rmarkdown
pandoc: Cannot decode byte '\xa9': 
Data.Text.Internal.Encoding.streamDecodeUtf8With: Invalid UTF-8 stream
Error: processing vignette 'Rmarkdown.Rmd' failed with diagnostics:
pandoc document conversion failed with error 1
--- failed re-building ‘Rmarkdown.Rmd’

--- re-building ‘code_chunks.Rmd’ using rmarkdown
convert: profile 'icc': 'RGB ': RGB color space not permitted on 
grayscale PNG `tmpout/p-chunk65-1.png' @ 
warning/png.c/MagickPNGWarningHandler/1672.
pandoc: Cannot decode byte '\xa9': 
Data.Text.Internal.Encoding.streamDecodeUtf8With: Invalid UTF-8 stream
Error: processing vignette 'code_chunks.Rmd' failed with diagnostics:
pandoc document conversion failed with error 1
--- failed re-building ‘code_chunks.Rmd’

\xa9 is a Latin-1 copyright sign.  The PNG error is seen only on macOS.
Unfortunately knitr/pandoc produce no debugging information, so this is 
all I know.

Answer 1

在我看来，关于\ xa9的错误是一场疯狂的追逐。

Pandoc说明已经改变。取代这个老节

header-includes:
-  \usepackage{xcolor}
-  \usepackage{fancybox}
-  \usepackage{calc}
-  \usepackage{subfig}

有了这个新的解决了这个问题。

header-includes:
- |
  ```{=latex}
  \usepackage{xcolor}
  \usepackage{fancybox}
  \usepackage{calc}
  \usepackage{subfig}
  ```

在那之后，我在Pandoc 2.6上取得了成功。

起初我以为我理解了这个问题，但后来它再次发生了，我完全重新输入了新的节，Pandoc不再给出错误了。所以我不知所措。

我还没有找到Macintosh上的PNG问题的答案。