[R] version plot problem

[PIKAL Petr]

Dear all

I have strange problem with plotting data.frame.

test <- structure(list(`Název Analýzy` = c("Kalcinát A", "Kalcinát A", 
"Kalcinát A", "Kalcinát A", "Kalcinát A", "Kalcinát A"), Prac = c("TB", 
"TB", "TB", "TB", "TB", "TB"), Vzorek = c("6101B", "6101B", "6101B", 
"6101B", "6101B", "6101B"), Datum = structure(c(1590624000, 1590624000, 
1590537600, 1590537600, 1590537600, 1590537600), class = c("POSIXct", 
"POSIXt"), tzone = "UTC"), Časm = structure(c(1590649200, 1590634800, 
1590620400, 1590606000, 1590591600, 1590577200), class = c("POSIXct", 
"POSIXt"), tzone = "UTC"), Time = structure(c(1590649200, 1590634800, 
1590620400, 1590606000, 1590591600, 1590577200), class = c("POSIXct", 
"POSIXt"), tzone = "UTC"), Kontrolor = c("BAROTOVÁ", "KRÁTKÁ", 
"KRÁTKÁ", "HOLASOVÁ", "HOLASOVÁ", "BAROTOVÁ"), SFM2 = c(239.4, 
221, 190.3, 215.7, 241.4, 214.8), SFM1 = c(48.7, 55.6, 52.9, 
50.1, 46.6, 54.4), `WI CIE` = c(94.2, 93, 92.4, 94.2, 96.3, 94.4
), `b*` = c(0.8, 1, 1, 0.8, 0.7, 0.8)), row.names = c(NA, 6L), class =
"data.frame")

plot(test)

is OK in R 4.0.0 but throws error in R 3.6.3, which is installed by our IT
> plot(test)
Error in plot.window(...) : need finite 'xlim' values
In addition: Warning messages:
1: In data.matrix(x) : NAs introduced by coercion
2: In data.matrix(x) : NAs introduced by coercion
3: In data.matrix(x) : NAs introduced by coercion
4: In

I know that latest version should be always used but I wonder if this
behavior is specific to 3.6.3 version and the only way is to reinstall R of
if there is some workaround like changing character columns to factor. I
found that it has something to do with character columns.

Best regards.
Petr
*************
platform       x86_64-w64-mingw32                                
arch           x86_64                                            
os             mingw32                                           
system         x86_64, mingw32                                   
status         Under development (unstable)                      
major          4                                                 
minor          0.0                                               
year           2020                                              
month          03                                                
day            08                                                
svn rev        77917                                             
language       R                                                 
version.string R Under development (unstable) (2020-03-08 r77917)
nickname       Unsuffered Consequences


platform       x86_64-w64-mingw32          
arch           x86_64                      
os             mingw32                     
system         x86_64, mingw32             
status                                     
major          3                           
minor          6.3                         
year           2020                        
month          02                          
day            29                          
svn rev        77875                       
language       R                           
version.string R version 3.6.3 (2020-02-29)
nickname       Holding the Windsock