When section numbering is on, tables and figures get two-part numbers like "1.2" (where 1 is the section number). When section numbering is off, they get simple sequential numbers like "2". There ought to be a way to get the latter behavior even when section numbering is on.

Related: #855

> xfun::session_info('rmarkdown')
R version 4.0.2 (2020-06-22)
Platform: x86_64-pc-linux-gnu (64-bit)
Running under: Ubuntu 20.10

Locale:
  LC_CTYPE=en_US.UTF-8       LC_NUMERIC=C              
  LC_TIME=en_US.UTF-8        LC_COLLATE=en_US.UTF-8    
  LC_MONETARY=en_US.UTF-8    LC_MESSAGES=en_US.UTF-8   
  LC_PAPER=en_US.UTF-8       LC_NAME=C                 
  LC_ADDRESS=C               LC_TELEPHONE=C            
  LC_MEASUREMENT=en_US.UTF-8 LC_IDENTIFICATION=C       

Package version:
  base64enc_0.1.3 digest_0.6.27   evaluate_0.14  
  glue_1.4.2      graphics_4.0.2  grDevices_4.0.2
  highr_0.8       htmltools_0.5.0 jsonlite_1.7.1 
  knitr_1.30      magrittr_2.0.1  markdown_1.1   
  methods_4.0.2   mime_0.9        rlang_0.4.9    
  rmarkdown_2.5   stats_4.0.2     stringi_1.5.3  
  stringr_1.4.0   tinytex_0.27    tools_4.0.2    
  utils_4.0.2     xfun_0.19       yaml_2.2.1     

Pandoc version: 2.9.2.1

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