Error(s) in re-building vignettes:
  ...
--- re-building ‘stplanr-od.Rmd’ using rmarkdown
Warning in engine$weave(file, quiet = quiet, encoding = enc) :
  Pandoc (>= 1.12.3) and/or pandoc-citeproc not available. Falling back to R Markdown v1.

Attaching package: 'dplyr'

The following objects are masked from 'package:stats':

    filter, lag

The following objects are masked from 'package:base':

    intersect, setdiff, setequal, union

Quitting from lines 213-217 (stplanr-od.Rmd) 
Error: processing vignette 'stplanr-od.Rmd' failed with diagnostics:
there is no package called 'webshot'
--- failed re-building ‘stplanr-od.Rmd’

--- re-building ‘stplanr-paper.Rmd’ using rmarkdown
Warning in engine$weave(file, quiet = quiet, encoding = enc) :
  Pandoc (>= 1.12.3) and/or pandoc-citeproc not available. Falling back to R Markdown v1.
--- finished re-building ‘stplanr-paper.Rmd’

--- re-building ‘stplanr-parallel.Rmd’ using rmarkdown
Warning in engine$weave(file, quiet = quiet, encoding = enc) :
  Pandoc (>= 1.12.3) and/or pandoc-citeproc not available. Falling back to R Markdown v1.
--- finished re-building ‘stplanr-parallel.Rmd’

--- re-building ‘stplanr-route-nets.Rmd’ using rmarkdown
Warning in engine$weave(file, quiet = quiet, encoding = enc) :
  Pandoc (>= 1.12.3) and/or pandoc-citeproc not available. Falling back to R Markdown v1.
Linking to GEOS 3.6.3, GDAL 2.2.4, PROJ 5.2.0
2020-06-04 16:27:31 constructing segments
2020-06-04 16:27:31 building geometry
2020-06-04 16:27:31 simplifying geometry
2020-06-04 16:27:31 aggregating flows
2020-06-04 16:27:31 rejoining segments into linestrings
--- finished re-building ‘stplanr-route-nets.Rmd’

--- re-building ‘stplanr-routing.Rmd’ using rmarkdown
Warning in engine$weave(file, quiet = quiet, encoding = enc) :
  Pandoc (>= 1.12.3) and/or pandoc-citeproc not available. Falling back to R Markdown v1.
--- finished re-building ‘stplanr-routing.Rmd’

--- re-building ‘stplanr.Rmd’ using rmarkdown
Warning in engine$weave(file, quiet = quiet, encoding = enc) :
  Pandoc (>= 1.12.3) and/or pandoc-citeproc not available. Falling back to R Markdown v1.
--- finished re-building ‘stplanr.Rmd’

SUMMARY: processing the following file failed:
  ‘stplanr-od.Rmd’

Error: Vignette re-building failed.
Execution halted