Error(s) in re-building vignettes:
  ...
--- re-building ‘selfmade_generic.Rmd’ using rmarkdown
Could not fetch https://latex.codecogs.com/png.image?%5Cdpi%7B110%7D&space;%5Cbg_white&space;y%20%5Cin%20%5Cmathbb%7BR%7D%5En
HttpExceptionRequest Request {
  host                 = "latex.codecogs.com"
  port                 = 443
  secure               = True
  requestHeaders       = []
  path                 = "/png.image"
  queryString          = "?%5Cdpi%7B110%7D&space;%5Cbg_white&space;y%20%5Cin%20%5Cmathbb%7BR%7D%5En"
  method               = "GET"
  proxy                = Nothing
  rawBody              = False
  redirectCount        = 10
  responseTimeout      = ResponseTimeoutDefault
  requestVersion       = HTTP/1.1
}
 (InternalException (HostCannotConnect "latex.codecogs.com" [Network.Socket.connect: <socket: 14>: does not exist (Connection refused)]))
Error: processing vignette ‘selfmade_generic.Rmd’ failed with diagnostics:
pandoc document conversion failed with error 61
--- failed re-building ‘selfmade_generic.Rmd’

SUMMARY: processing the following file failed:
  ‘selfmade_generic.Rmd’

Error: Vignette re-building failed.
Execution halted
Error(s) in re-building vignettes:
--- re-building ‘selfmade_generic.Rmd’ using rmarkdown
Could not fetch https://latex.codecogs.com/png.image?%5Cdpi%7B110%7D&space;%5Cbg_white&space;L_2
HttpExceptionRequest Request {
  host                 = "latex.codecogs.com"
  port                 = 443
  secure               = True
  requestHeaders       = []
  path                 = "/png.image"
  queryString          = "?%5Cdpi%7B110%7D&space;%5Cbg_white&space;L_2"
  method               = "GET"
  proxy                = Nothing
  rawBody              = False
  redirectCount        = 10
  responseTimeout      = ResponseTimeoutDefault
  requestVersion       = HTTP/1.1
  proxySecureMode      = ProxySecureWithConnect
}
 (InternalException (HostCannotConnect "latex.codecogs.com" [Network.Socket.connect: <socket: 14>: does not exist (Connection refused)]))
Error: processing vignette 'selfmade_generic.Rmd' failed with diagnostics:
pandoc document conversion failed with error 61
--- failed re-building ‘selfmade_generic.Rmd’

SUMMARY: processing the following file failed:
  ‘selfmade_generic.Rmd’

Error: Vignette re-building failed.
Execution halted
Error(s) in re-building vignettes:
--- re-building ‘selfmade_generic.Rmd’ using rmarkdown
Could not fetch https://latex.codecogs.com/png.image?%5Cdpi%7B110%7D&space;%5Cbg_white&space;y
HttpExceptionRequest Request {
  host                 = "latex.codecogs.com"
  port                 = 443
  secure               = True
  requestHeaders       = []
  path                 = "/png.image"
  queryString          = "?%5Cdpi%7B110%7D&space;%5Cbg_white&space;y"
  method               = "GET"
  proxy                = Nothing
  rawBody              = False
  redirectCount        = 10
  responseTimeout      = ResponseTimeoutDefault
  requestVersion       = HTTP/1.1
}
 (InternalException (HostCannotConnect "latex.codecogs.com" [Network.Socket.connect: <socket: 14>: does not exist (Connection refused)]))
Error: processing vignette 'selfmade_generic.Rmd' failed with diagnostics:
pandoc document conversion failed with error 61
--- failed re-building ‘selfmade_generic.Rmd’

SUMMARY: processing the following file failed:
  ‘selfmade_generic.Rmd’

Error: Vignette re-building failed.
Execution halted
Error(s) in re-building vignettes:
--- re-building 'selfmade_generic.Rmd' using rmarkdown
Could not fetch https://latex.codecogs.com/png.image?%5Cdpi%7B110%7D&space;%5Cbg_white&space;L_2
HttpExceptionRequest Request {
  host                 = "latex.codecogs.com"
  port                 = 443
  secure               = True
  requestHeaders       = []
  path                 = "/png.image"
  queryString          = "?%5Cdpi%7B110%7D&space;%5Cbg_white&space;L_2"
  method               = "GET"
  proxy                = Nothing
  rawBody              = False
  redirectCount        = 10
  responseTimeout      = ResponseTimeoutDefault
  requestVersion       = HTTP/1.1
}
 (InternalException (HostCannotConnect "latex.codecogs.com" [Network.Socket.connect: <socket: 848>: failed (Connection refused (WSAECONNREFUSED))]))
Error: processing vignette 'selfmade_generic.Rmd' failed with diagnostics:
pandoc document conversion failed with error 61
--- failed re-building 'selfmade_generic.Rmd'

SUMMARY: processing the following file failed:
  'selfmade_generic.Rmd'

Error: Vignette re-building failed.
Execution halted
Package required but not available: 'lme4'

Packages suggested but not available for checking:
  'knitr', 'rmarkdown', 'gamm4', 'lmerTest'

VignetteBuilder package required for checking but not installed: 'knitr'

See section 'The DESCRIPTION file' in the 'Writing R Extensions'
manual.
Error(s) in re-building vignettes:
--- re-building 'selfmade_generic.Rmd' using rmarkdown
Error: processing vignette 'selfmade_generic.Rmd' failed with diagnostics:
only `math_method = 'mathjax'` is supported with earlier version than Pandoc 2.0 
--- failed re-building 'selfmade_generic.Rmd'

SUMMARY: processing the following file failed:
  'selfmade_generic.Rmd'

Error: Vignette re-building failed.
Execution halted
Error(s) in re-building vignettes:
--- re-building 'selfmade_generic.Rmd' using rmarkdown
Error: processing vignette 'selfmade_generic.Rmd' failed with diagnostics:
only `math_method = 'mathjax'` is supported with earlier version than Pandoc 2.0 
--- failed re-building 'selfmade_generic.Rmd'

SUMMARY: processing the following file failed:
  'selfmade_generic.Rmd'

Error: Vignette re-building failed.
Execution halted