help needed installing linuxcnc as a simulator on my debian buster laptop

Error in startup script: bad pad value "3m": must be positive screen distance
    while executing
"pack $w.msg -in $w.top -side right -expand 1 -fill both -padx 3m -pady 3m"
    (procedure "tk_dialog" line 65)
    invoked from within
"tk_dialog .d [msgcat::mc "Copy Configuration?"] [msgcat::mc "Would you like to copy the %s configuration to your home directory so you can customize i..."
    (procedure "prompt_copy" line 3)
    invoked from within
"prompt_copy $::inifile"
    invoked from within
"if [ok_to_copy_config $::inifile] {
            set copied_inifile [prompt_copy $::inifile]
            if {$copied_inifile == ""} {
                c..."
    ("while" body line 6)
    invoked from within
"while {1} {
    focus $::tree
    vwait ::choice

    if { $::choice == "OK" } {
        if [ok_to_copy_config $::inifile] {
            set copied_in..."
    (file "/usr/lib/tcltk/linuxcnc/bin/pickconfig.tcl" line 875)