Learnr shiny app failing to deploy on shinyapps.io

I have been building and deploying an R tutorial on shinyapps.io for weeks now. The Rmd file is 114 KB and the corresponding HTML file is 530.6 KB. It builds fine and the testing for the exercises passes locally. All of sudden today I started experiencing failures while deploying. It goes through all the steps:
image
However, the actual page fails to be displayed with error:


The logs for that instance say:

2021-02-11T05:17:49.664364+00:00 shinyapps[3610310]: Using jsonlite for JSON processing
2021-02-11T05:17:49.667775+00:00 shinyapps[3610310]:
2021-02-11T05:17:49.451664+00:00 shinyapps[3610310]: Using pandoc: /opt/connect/ext/pandoc/2.11
2021-02-11T05:17:49.667776+00:00 shinyapps[3610310]: Starting R with process ID: '62'
2021-02-11T05:17:53.090076+00:00 shinyapps[3610310]: Killed
2021-02-11T05:17:53.091651+00:00 shinyapps[3610310]: pandoc document conversion failed with error 137
2021-02-11T05:17:53.091660+00:00 shinyapps[3610310]: Execution halted
2021-02-11T05:17:53.091650+00:00 shinyapps[3610310]: Error in value[3L] :
2021-02-11T05:17:53.091652+00:00 shinyapps[3610310]: Calls: local ... tryCatch -> tryCatchList -> tryCatchOne ->
2021-02-11T05:29:33.400685+00:00 shinyapps[3610310]: Running on host: e47679d834dd
2021-02-11T05:29:33.408856+00:00 shinyapps[3610310]: Server version: 1.8.6.1
2021-02-11T05:29:33.408871+00:00 shinyapps[3610310]: LANG: en_CA.UTF-8
2021-02-11T05:29:33.408873+00:00 shinyapps[3610310]: R version: 4.0.3
2021-02-11T05:29:33.408935+00:00 shinyapps[3610310]: jsonlite version: 1.7.2
2021-02-11T05:29:33.408936+00:00 shinyapps[3610310]: RJSONIO version: (none)
2021-02-11T05:29:33.408884+00:00 shinyapps[3610310]: httpuv version: 1.5.5
2021-02-11T05:29:33.408875+00:00 shinyapps[3610310]: shiny version: 1.6.0
2021-02-11T05:29:33.408947+00:00 shinyapps[3610310]: htmltools version: 0.5.1.1
2021-02-11T05:29:33.408893+00:00 shinyapps[3610310]: rmarkdown version: 2.6
2021-02-11T05:29:33.408926+00:00 shinyapps[3610310]: knitr version: 1.31
2021-02-11T05:29:33.409196+00:00 shinyapps[3610310]: Using pandoc: /opt/connect/ext/pandoc/2.11
2021-02-11T05:29:33.619033+00:00 shinyapps[3610310]: Using jsonlite for JSON processing
2021-02-11T05:29:33.622493+00:00 shinyapps[3610310]:
2021-02-11T05:29:33.622493+00:00 shinyapps[3610310]: Starting R with process ID: '25'
2021-02-11T05:29:37.018369+00:00 shinyapps[3610310]: Killed
2021-02-11T05:29:37.019927+00:00 shinyapps[3610310]: Error in value[3L] :
2021-02-11T05:29:37.019929+00:00 shinyapps[3610310]: pandoc document conversion failed with error 137
2021-02-11T05:29:37.019930+00:00 shinyapps[3610310]: Calls: local ... tryCatch -> tryCatchList -> tryCatchOne ->
2021-02-11T05:29:37.019958+00:00 shinyapps[3610310]: Execution halted
2021-02-11T05:29:37.090212+00:00 shinyapps[system]: Out of memory!
2021-02-11T05:29:41.858112+00:00 shinyapps[3610310]: Running on host: e47679d834dd
2021-02-11T05:29:41.866132+00:00 shinyapps[3610310]: Server version: 1.8.6.1
2021-02-11T05:29:41.866211+00:00 shinyapps[3610310]: shiny version: 1.6.0
2021-02-11T05:29:41.866228+00:00 shinyapps[3610310]: httpuv version: 1.5.5
2021-02-11T05:29:41.866229+00:00 shinyapps[3610310]: rmarkdown version: 2.6
2021-02-11T05:29:41.866210+00:00 shinyapps[3610310]: R version: 4.0.3
2021-02-11T05:29:41.866305+00:00 shinyapps[3610310]: RJSONIO version: (none)
2021-02-11T05:29:41.866155+00:00 shinyapps[3610310]: LANG: en_CA.UTF-8
2021-02-11T05:29:42.072858+00:00 shinyapps[3610310]:
2021-02-11T05:29:41.866282+00:00 shinyapps[3610310]: jsonlite version: 1.7.2
2021-02-11T05:29:42.069536+00:00 shinyapps[3610310]: Using jsonlite for JSON processing
2021-02-11T05:29:42.072860+00:00 shinyapps[3610310]: Starting R with process ID: '61'
2021-02-11T05:29:41.866241+00:00 shinyapps[3610310]: knitr version: 1.31
2021-02-11T05:29:41.866314+00:00 shinyapps[3610310]: htmltools version: 0.5.1.1
2021-02-11T05:29:41.866569+00:00 shinyapps[3610310]: Using pandoc: /opt/connect/ext/pandoc/2.11
2021-02-11T05:29:45.433734+00:00 shinyapps[3610310]: Killed
2021-02-11T05:29:45.443555+00:00 shinyapps[3610310]: Calls: local ... tryCatch -> tryCatchList -> tryCatchOne ->
2021-02-11T05:29:45.443552+00:00 shinyapps[3610310]: Error in value[3L] :
2021-02-11T05:29:45.443554+00:00 shinyapps[3610310]: pandoc document conversion failed with error 137
2021-02-11T05:29:45.443555+00:00 shinyapps[3610310]: Execution halted
2021-02-11T05:29:48.058177+00:00 shinyapps[system]: Out of memory!

The instance is large (1GB) and it does not matter if I enable/disable the package cache.
What could it be killing the pandoc document conversion?
How do I troubleshoot and fix something like this?
The pandoc conversions from Rmd to HTML is very opaque to me.
Thanks,
Pablo

You could add some logging statements in your Rmd, to see till how far everything is going well and so which line might be the problem.

Did you have a look at the Troubleshooting already?