Error(s) in re-building vignettes:
--- re-building ‘help.Rmd’ using rmarkdown
trying URL 'https://cloud.r-project.org/bin/macosx/contrib/4.0/ps_1.3.2.tgz'
Content type 'application/x-gzip' length 207845 bytes (202 KB)
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downloaded 202 KB

trying URL 'https://cloud.r-project.org/bin/macosx/contrib/4.0/processx_3.4.2.tgz'
Content type 'application/x-gzip' length 252491 bytes (246 KB)
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downloaded 246 KB

trying URL 'https://cloud.r-project.org/bin/macosx/contrib/4.0/callr_3.4.3.tgz'
Content type 'application/x-gzip' length 389412 bytes (380 KB)
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downloaded 380 KB

trying URL 'https://cloud.r-project.org/bin/macosx/contrib/4.0/prettyunits_1.1.1.tgz'
Content type 'application/x-gzip' length 34788 bytes (33 KB)
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downloaded 33 KB

trying URL 'https://cloud.r-project.org/bin/macosx/contrib/4.0/backports_1.1.5.tgz'
Content type 'application/x-gzip' length 55702 bytes (54 KB)
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downloaded 54 KB

trying URL 'https://cloud.r-project.org/bin/macosx/contrib/4.0/assertthat_0.2.1.tgz'
Content type 'application/x-gzip' length 52472 bytes (51 KB)
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downloaded 51 KB

trying URL 'https://cloud.r-project.org/bin/macosx/contrib/4.0/glue_1.3.2.tgz'
Content type 'application/x-gzip' length 138348 bytes (135 KB)
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downloaded 135 KB

trying URL 'https://cloud.r-project.org/bin/macosx/contrib/4.0/fansi_0.4.1.tgz'
Content type 'application/x-gzip' length 210403 bytes (205 KB)
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downloaded 205 KB

trying URL 'https://cloud.r-project.org/bin/macosx/contrib/4.0/desc_1.2.0.tgz'
Content type 'application/x-gzip' length 279598 bytes (273 KB)
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downloaded 273 KB

trying URL 'https://cloud.r-project.org/bin/macosx/contrib/4.0/pkgbuild_1.0.6.tgz'
Content type 'application/x-gzip' length 135240 bytes (132 KB)
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downloaded 132 KB

trying URL 'https://cloud.r-project.org/bin/macosx/contrib/4.0/rprojroot_1.3-2.tgz'
Content type 'application/x-gzip' length 78792 bytes (76 KB)
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downloaded 76 KB

trying URL 'https://cloud.r-project.org/bin/macosx/contrib/4.0/rstudioapi_0.11.tgz'
Content type 'application/x-gzip' length 254966 bytes (248 KB)
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downloaded 248 KB

trying URL 'https://cloud.r-project.org/bin/macosx/contrib/4.0/cli_2.0.2.tgz'
Content type 'application/x-gzip' length 393956 bytes (384 KB)
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downloaded 384 KB

trying URL 'https://cloud.r-project.org/bin/macosx/contrib/4.0/crayon_1.3.4.tgz'
Content type 'application/x-gzip' length 748246 bytes (730 KB)
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downloaded 730 KB

trying URL 'https://cloud.r-project.org/bin/macosx/contrib/4.0/digest_0.6.25.tgz'
Content type 'application/x-gzip' length 245652 bytes (239 KB)
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downloaded 239 KB

trying URL 'https://cloud.r-project.org/bin/macosx/contrib/4.0/ellipsis_0.3.0.tgz'
Content type 'application/x-gzip' length 33038 bytes (32 KB)
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downloaded 32 KB

trying URL 'https://cloud.r-project.org/bin/macosx/contrib/4.0/evaluate_0.14.tgz'
Content type 'application/x-gzip' length 74053 bytes (72 KB)
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downloaded 72 KB

trying URL 'https://cloud.r-project.org/bin/macosx/contrib/4.0/magrittr_1.5.tgz'
Content type 'application/x-gzip' length 152755 bytes (149 KB)
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downloaded 149 KB

trying URL 'https://cloud.r-project.org/bin/macosx/contrib/4.0/pkgload_1.0.2.tgz'
Content type 'application/x-gzip' length 144709 bytes (141 KB)
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downloaded 141 KB

trying URL 'https://cloud.r-project.org/bin/macosx/contrib/4.0/praise_1.0.0.tgz'
Content type 'application/x-gzip' length 16131 bytes (15 KB)
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downloaded 15 KB

trying URL 'https://cloud.r-project.org/bin/macosx/contrib/4.0/R6_2.4.1.tgz'
Content type 'application/x-gzip' length 57308 bytes (55 KB)
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downloaded 55 KB

trying URL 'https://cloud.r-project.org/bin/macosx/contrib/4.0/rlang_0.4.5.tgz'
Content type 'application/x-gzip' length 1178352 bytes (1.1 MB)
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downloaded 1.1 MB

trying URL 'https://cloud.r-project.org/bin/macosx/contrib/4.0/withr_2.1.2.tgz'
Content type 'application/x-gzip' length 151440 bytes (147 KB)
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downloaded 147 KB

trying URL 'https://cloud.r-project.org/bin/macosx/contrib/4.0/pls_2.7-2.tgz'
Content type 'application/x-gzip' length 1228280 bytes (1.2 MB)
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downloaded 1.2 MB

trying URL 'https://cloud.r-project.org/bin/macosx/contrib/4.0/testthat_2.3.2.tgz'
Content type 'application/x-gzip' length 2368217 bytes (2.3 MB)
==================================================
downloaded 2.3 MB

trying URL 'https://cloud.r-project.org/bin/macosx/contrib/4.0/apercu_0.2.4.tgz'
Content type 'application/x-gzip' length 26005 bytes (25 KB)
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downloaded 25 KB

* installing *source* package ‘dummyPackage’ ...
** using staged installation
** R
** byte-compile and prepare package for lazy loading
** help
*** installing help indices
** building package indices
** testing if installed package can be loaded from temporary location
** testing if installed package can be loaded from final location
** testing if installed package keeps a record of temporary installation path
* DONE (dummyPackage)
trying URL 'https://cloud.r-project.org/bin/macosx/contrib/4.0/apercu_0.2.4.tgz'
Content type 'application/x-gzip' length 26005 bytes (25 KB)
==================================================
downloaded 25 KB

trying URL 'https://cloud.r-project.org/bin/macosx/contrib/4.0/apercu_0.2.4.tgz'
Content type 'application/x-gzip' length 26005 bytes (25 KB)
==================================================
downloaded 25 KB

trying URL 'https://cloud.r-project.org/bin/macosx/contrib/4.0/apercu_0.2.4.tgz'
Content type 'application/x-gzip' length 26005 bytes (25 KB)
==================================================
downloaded 25 KB

dyld: lazy symbol binding failed: Symbol not found: ____chkstk_darwin
  Referenced from: /usr/local/bin/pandoc (which was built for Mac OS X 10.15)
  Expected in: /usr/lib/libSystem.B.dylib

dyld: Symbol not found: ____chkstk_darwin
  Referenced from: /usr/local/bin/pandoc (which was built for Mac OS X 10.15)
  Expected in: /usr/lib/libSystem.B.dylib

Error: processing vignette 'help.Rmd' failed with diagnostics:
pandoc document conversion failed with error 6
--- failed re-building ‘help.Rmd’

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

Error: Vignette re-building failed.
Execution halted