[3.12] gh-78955: Use user-selected color theme for Help => IDLE Doc (GH-9502) (#118632)

gh-78955: Use user-selected color theme for Help => IDLE Doc (GH-9502)
(cherry picked from commit 7758be4318)

Co-authored-by: Terry Jan Reedy <tjreedy@udel.edu>

Lib/idlelib/News3.txt

@@ -4,6 +4,8 @@ Released after 2023-10-02
 =========================
 
 
+gh-78955: Use user-selected color theme for Help => IDLE Doc.
+
 gh-96905: In idlelib code, stop redefining built-ins 'dict' and 'object'.
 
 gh-72284: Improve the lists of features, editor key bindings,

Lib/idlelib/help.py

@@ -33,6 +33,7 @@
 from tkinter import font as tkfont
 
 from idlelib.config import idleConf
+from idlelib.colorizer import color_config
 
 ## About IDLE ##
 
@@ -177,14 +178,16 @@ def __init__(self, parent, filename):
 
         normalfont = self.findfont(['TkDefaultFont', 'arial', 'helvetica'])
         fixedfont = self.findfont(['TkFixedFont', 'monaco', 'courier'])
+        color_config(self)
         self['font'] = (normalfont, 12)
         self.tag_configure('em', font=(normalfont, 12, 'italic'))
         self.tag_configure('h1', font=(normalfont, 20, 'bold'))
         self.tag_configure('h2', font=(normalfont, 18, 'bold'))
         self.tag_configure('h3', font=(normalfont, 15, 'bold'))
-        self.tag_configure('pre', font=(fixedfont, 12), background='#f6f6ff')
+        self.tag_configure('pre', font=(fixedfont, 12))
+        preback = self['selectbackground']
         self.tag_configure('preblock', font=(fixedfont, 10), lmargin1=25,
-                borderwidth=1, relief='solid', background='#eeffcc')
+                           background=preback)
         self.tag_configure('l1', lmargin1=25, lmargin2=25)
         self.tag_configure('l2', lmargin1=50, lmargin2=50)
         self.tag_configure('l3', lmargin1=75, lmargin2=75)

Misc/NEWS.d/next/IDLE/2018-09-23-01-36-39.bpo-34774.VeM-X-.rst

@@ -0,0 +1 @@
+Use user-selected color theme for Help => IDLE Doc.