title: Python tkinter on Mac: buttons don't highlight until after file browser opened
body: <p>I'm working on a Python tkinter app on mac, and have run into a strange issue. Though clicking on buttons call their functions as they should, I've found that the buttons don't flash a different color when the mouse is depressed (which would be helpful to visually indicate that the button has registered as clicked).</p>
  <p>However, after I open a file browser with <code>tk.filedialog.askdirectory()</code>, all buttons in the app turn blue while the mouse is depressed.</p>
  <p>Can you give me any insight as to why this is, and could you let me know how to make this occur by default?</p>
  <p>Edit: Here's an example of a simple test program I made, in which the same issue appears:</p>
  <pre><code>import tkinter as tk
  from tkinter import filedialog as fd
  
  def addText():
      label = tk.Label(labelsFrame, text=&quot;This is text.&quot;)
      label.pack()
  
  def openBrowser():
      fd.askdirectory()
  
  root = tk.Tk()
  
  buttonsFrame = tk.Frame(root)
  buttonsFrame.grid(row=0, column=0)
  
  labelsFrame = tk.Frame(root)
  labelsFrame.grid(row=1, column=0)
  
  button1 = tk.Button(buttonsFrame, text=&quot;Add Text&quot;, command=addText)
  button1.grid(row=0, column=0)
  
  button2 = tk.Button(buttonsFrame, text=&quot;Open Browser&quot;, command=openBrowser)
  button2.grid(row=0, column=1)
  
  tk.mainloop()
  </code></pre>