Can't get content for FTP directory listing about httr HOT 4 CLOSED

library(httr)

# ftp site obtained from https://dlptest.com/ftp-test/
ftp_list <-
  GET("ftp://ftp.dlptest.com/",
      authenticate("dlpuser", "rNrKYTX9g7z3RgJRmxWuGHbeu"),
      dirlistonly = TRUE)

## this doesn't work and throws an error:
content(ftp_list)
#> Error in x$headers[["Content-Type"]]: subscript out of bounds

## this does work:
cat(rawToChar(ftp_list$content))
#> drwxr-xr-x    3 1001     1001           16 Nov 01 19:42 11
#> -rw-r--r--    1 1001     1001     37032115 Nov 01 19:45 CGR_WAV_102023.wav
#> -rw-r--r--    1 1001     1001          718 Nov 01 19:40 Export_PostVenta_64552.csv
#> -rw-r--r--    1 1001     1001         1492 Nov 01 19:40 Export_PostVenta_64553.csv
#> -rw-r--r--    1 1001     1001          878 Nov 01 19:44 Export_PostVenta_64612.csv
#> -rw-r--r--    1 1001     1001         1169 Nov 01 19:44 Export_PostVenta_64613.csv
#> -rw-r--r--    1 1001     1001        27781 Nov 01 19:40 Export_PostVenta_64711.csv
#> -rw-r--r--    1 1001     1001          187 Nov 01 19:40 Export_PostVenta_64712.csv
#> -rw-r--r--    1 1001     1001          168 Nov 01 19:40 Export_PostVenta_64713.csv
#> -rw-r--r--    1 1001     1001          345 Nov 01 19:44 Export_PostVenta_64714.csv
#> -rw-r--r--    1 1001     1001          178 Nov 01 19:44 Export_PostVenta_64715.csv
#> -rw-r--r--    1 1001     1001     10485760 Nov 01 19:44 NetAllyTest.txt
#> -rw-r--r--    1 1001     1001         1149 Nov 01 19:43 TestUpload.kml
#> drwxr-xr-x    3 1001     1001           18 Nov 01 19:40 Vorne
#> -rw-r--r--    1 1001     1001       593920 Nov 01 19:41 \conexao.sdf
#> -rw-r--r--    1 1001     1001        10000 Nov 01 19:45 _11471977
#> drwxr-xr-x    2 1001     1001           29 Nov 01 19:40 input
#> -rw-r--r--    1 1001     1001         6895 Nov 01 19:43 test-cron-2023-11-01.xlsx
#> -rw-r--r--    1 1001     1001          144 Nov 01 19:40 test.zip