rmarkdown 2.29

• find_external_resources() now correctly detects knitr child document provided with option like child = c("child.Rmd") (thanks, @rempsyc, #2574).

• knit_params_ask() uses a select input for parameters which allow multiple selected values (#2576). Previously, a radio input was incorrectly used when the parameter had a small number of choices.

  params:
      primaries:
          choices: ["red", "yellow", "blue"]
          multiple: true

  When multiple is not enabled, parameter configuration still uses radio when there are fewer than five choices.

  The input parameter field can still be used to force the configuration control.

  params:
      grade:
          input: radio
          choices: ["A", "B", "C", "D", "F"]