tkinter (ttk) combobox dropdown text is white on white

[MRAB]

On 2018-06-06 02:42, Terry Reedy wrote:
> On 6/3/2018 3:54 PM, Jim Lee wrote:
>> Given the following snippet (Python 3.6.5, Tk 8.6.8):
> 
> What OS? Likely not Windows
> 
Already answered: Linux (Fedora 28, MATE desktop).

>> import tkinter as tk
>> from tkinter import ttk
>> 
>> root = tk.Tk()
>> cb = ttk.Combobox(root)
>> cb.grid(row=0, column=0, sticky='NSEW')
>> cb['values'] = ['one', 'two', 'three', 'four']
>> root.mainloop()
>> 
>> The text of the values in the combobox dropdown list is white on 
>> white.
> 
> Win 10, 3.7.0b5: I see black on white with blue selection background.
> 
>      The *selected* item in the list is white on light grey, but all
>> the unselected items are invisible (white on white).  I have played with 
>> themes and styles, and can alter the foreground and background colors of 
>> the combobox itself, but I cannot figure out how to alter the appearance 
>> of entries in the dropdown list. Any pointers?
> 
I haven't had a problem with it on Windows.