Error(s) in re-building vignettes:
--- re-building 'FFD-tibble-how-to.Rmd' using rmarkdown
Initiating curl with CURL_SSL_BACKEND: openssl
trying URL 'http://mba.tuck.dartmouth.edu/pages/faculty/ken.french/ftp/F-F_Research_Data_Factors_CSV.zip'
trying URL 'http://mba.tuck.dartmouth.edu/pages/faculty/ken.french/ftp/F-F_Momentum_Factor_CSV.zip'
--- finished re-building 'FFD-tibble-how-to.Rmd'

--- re-building 'FFD-xts-how-to.Rmd' using rmarkdown
Initiating curl with CURL_SSL_BACKEND: openssl
Quitting from lines 37-39 (FFD-xts-how-to.Rmd) 
Error: processing vignette 'FFD-xts-how-to.Rmd' failed with diagnostics:
Timeout was reached: [mba.tuck.dartmouth.edu] Connection timeout after 10002 ms
--- failed re-building 'FFD-xts-how-to.Rmd'

SUMMARY: processing the following file failed:
  'FFD-xts-how-to.Rmd'

Error: Vignette re-building failed.
Execution halted