Error(s) in re-building vignettes:
  ...
--- re-building ‘Generalized-RF.Rmd’ using rmarkdown
[WARNING] Deprecated: --highlight-style. Use --syntax-highlighting instead.
--- finished re-building ‘Generalized-RF.Rmd’

--- re-building ‘Robinson-Foulds.Rmd’ using rmarkdown
[WARNING] Deprecated: --highlight-style. Use --syntax-highlighting instead.
--- finished re-building ‘Robinson-Foulds.Rmd’

--- re-building ‘Using-TreeDist.Rmd’ using rmarkdown
[WARNING] Deprecated: --highlight-style. Use --syntax-highlighting instead.
--- finished re-building ‘Using-TreeDist.Rmd’

--- re-building ‘compare-treesets.Rmd’ using rmarkdown
[WARNING] Deprecated: --highlight-style. Use --syntax-highlighting instead.
Could not fetch https://raw.githubusercontent.com/citation-style-language/styles/master/apa-old-doi-prefix.csl
HttpExceptionRequest Request {
  host                 = "raw.githubusercontent.com"
  port                 = 443
  secure               = True
  requestHeaders       = []
  path                 = "/citation-style-language/styles/master/apa-old-doi-prefix.csl"
  queryString          = ""
  method               = "GET"
  proxy                = Nothing
  rawBody              = False
  redirectCount        = 10
  responseTimeout      = ResponseTimeoutDefault
  requestVersion       = HTTP/1.1
  proxySecureMode      = ProxySecureWithConnect
}
 ConnectionTimeout
Error: processing vignette 'compare-treesets.Rmd' failed with diagnostics:
pandoc document conversion failed with error 61
--- failed re-building ‘compare-treesets.Rmd’

--- re-building ‘different-leaves.Rmd’ using rmarkdown
[WARNING] Deprecated: --highlight-style. Use --syntax-highlighting instead.
--- finished re-building ‘different-leaves.Rmd’

--- re-building ‘information.Rmd’ using rmarkdown
[WARNING] Deprecated: --highlight-style. Use --syntax-highlighting instead.
--- finished re-building ‘information.Rmd’

--- re-building ‘landscapes.Rmd’ using rmarkdown
[WARNING] Deprecated: --highlight-style. Use --syntax-highlighting instead.
--- finished re-building ‘landscapes.Rmd’

--- re-building ‘treespace.Rmd’ using rmarkdown
[WARNING] Deprecated: --highlight-style. Use --syntax-highlighting instead.
--- finished re-building ‘treespace.Rmd’

--- re-building ‘using-distances.Rmd’ using rmarkdown
[WARNING] Deprecated: --highlight-style. Use --syntax-highlighting instead.
--- finished re-building ‘using-distances.Rmd’

SUMMARY: processing the following file failed:
  ‘compare-treesets.Rmd’

Error: Vignette re-building failed.
Execution halted