From c50767fd277e82ee50db319443b2716f988fc0a7 Mon Sep 17 00:00:00 2001
From: Matthias Bussonnier <bussonniermatthias@gmail.com>
Date: Mon, 6 Dec 2021 15:33:02 -0800
Subject: [PATCH] Backport PR #13372: use full-alpha transparency on dvipng
 rendered LaTeX

---
 IPython/lib/latextools.py | 23 ++++++++++++++++++++---
 IPython/utils/timing.py   |  1 -
 2 files changed, 20 insertions(+), 4 deletions(-)

diff --git a/IPython/lib/latextools.py b/IPython/lib/latextools.py
index cbcc7d9639e..f976f2edb13 100644
--- a/IPython/lib/latextools.py
+++ b/IPython/lib/latextools.py
@@ -151,9 +151,26 @@ def latex_to_png_dvipng(s, wrap, color='Black', scale=1.0):
 
             resolution = round(150*scale)
             subprocess.check_call(
-                ["dvipng", "-T", "tight", "-D", str(resolution), "-z", "9",
-                 "-bg", "transparent", "-o", outfile, dvifile, "-fg", color],
-                 cwd=workdir, stdout=devnull, stderr=devnull)
+                [
+                    "dvipng",
+                    "-T",
+                    "tight",
+                    "-D",
+                    str(resolution),
+                    "-z",
+                    "9",
+                    "-bg",
+                    "Transparent",
+                    "-o",
+                    outfile,
+                    dvifile,
+                    "-fg",
+                    color,
+                ],
+                cwd=workdir,
+                stdout=devnull,
+                stderr=devnull,
+            )
 
         with open(outfile, "rb") as f:
             return f.read()
diff --git a/IPython/utils/timing.py b/IPython/utils/timing.py
index 32741acdd9c..92f6883c4af 100644
--- a/IPython/utils/timing.py
+++ b/IPython/utils/timing.py
@@ -62,7 +62,6 @@ def clock2():
         Similar to clock(), but return a tuple of user/system times."""
         return resource.getrusage(resource.RUSAGE_SELF)[:2]
 
-
 else:
     # There is no distinction of user/system time under windows, so we just use
     # time.perff_counter() for everything...