Times New Roman font becomes italic after windows 11 update 26200.7171

[dolphin]

Operating system: windows 11 25H2 OS Build 26200.7171
Browser version: 33.9.1
32-bit or 64-bit browser?: 64

Updated windows 11 on three different computers with a security patch today:
2025-11 Security Update (KB5068861) (26200.7171)

After the update, Pale Moon shows Times New Roman font text as italic instead of normal.

For a CSS class:
font-family: Times New Roman, Times, serif;
font-size: 16px;
line-height: 22px;
padding: 8px;

Pale Moon is now showing that as italic.

Windows build 26200.6899 and previous for the last 20 years showed it as normal (no change to html/css).

Any idea why the windows 11 update is now causing Pale Moon to show Times New Roman as italic?
Chrome/Edge/Firefox still show Times New Roman as normal, not italic with the above css class.

I tried adding
font-style: normal !important;
and Pale Moon still shows Times New Roman text as italic.

Arial and other fonts show normal still.

Disabled hardware acceleration with no change.

[Goodydino]

Maybe that font is damaged? Can you reinstall it?

[dolphin]

Just had a 4th computer update.
Yesterday it was fine with Pale Moon; now after the windows automatic update, it also is showing Times New Roman as italic in pale moon.

Looking at c:\windows\fonts, opening Times New Roman and then clicking on properties on
Times New Roman Regular

I see that that ttf file has been updated with the windows update.
times.ttf
Created: Tuesday, ‎November ‎11, ‎2025, ‏‎8:25:27 PM
Modified: ‎Tuesday, ‎November ‎11, ‎2025, ‏‎8:25:27 PM

Details:
File Version 7.10
Authors Monotype Type Drawing Office
Copyright 2020 The Monotype Corporation
License description Microsoft supplied font.

(The italic versions of Times New Roman are version 7.05 modified in April of 2024.)

Since Chrome and Firefox are showing normal Times New Roman fine still, I'm not sure what to make of whatever changed in that TTF file with the windows update ???

[Moonchild]

Maybe report this to Microsoft? Clearly there's something weird going on.
I'm not even sure why they would have an italic font variant in the "regular" base font file, if that's what's going on, or perhaps it's actually broken and doesn't pass the font sanitizer in Pale Moon having it fall back to the italic variant as the closest family match?
Is there anything in the error console?

[dolphin]

Nothing in Pale Moon Error Console

I can't find another program on the windows computers that has a problem with the new Times New Roman font -- it's fine in the other browsers, notepad, open office writer, etc.

Pale Moon has Default Font: Times New Roman Size: 16 under Preferences > Content.

I created a new html file with no css styling at all, and simply the word Test within the body tags, and Pale Moon shows it as italic.

[RealityRipple]

I coped times.ttf, timesbd.ttf, timesbi.ttf, and timesi.ttf from my pre-KB5068861 VM (no italics), then installed KB5068861. Coped the same files again and compared them; they're byte-for-byte identical. Confirmed the behavior though, and in the developer tools, when you analyze the element and go to the font tab, it identifies it as "times new roman italic" used as "times new roman". definitely behaves like some response order change or something of that sort.

Since it was just released and because I was curious if it'd change anything, I just compiled with VS2026 (14.50.35710); no change in behavior.

[Moonchild]

If the font files are identical, then that makes it an even weirder thing.
Perhaps it is a bug in the Windows SDK that Pale Moon is built against? If someone has time and opportunity then maybe build with either a newer or older SDK and see...

[RealityRipple]

I'll try some older ones tomorrow; got the latest release 10.0.26100.0 (technically .6901) on VC145 (14.50) already covered.

Confirmed behavior on 22621(.5040) with VC143 (14.44).

Aaand... VC142's support was dropped; it doesn't run.

[Robbie]

We have a software product where we have embedded Firefox 38 and have also ran into this italic font issue after the Windows update. While searching through Google I found this thread, which was useful. We are still investigating the issue but I wanted to share what we have found so far as it might be useful for this project as well.

The Windows update installs a new version of the Times New Roman regular and bold font faces (times.ttf and timesbd.ttf). Before the update the version of the font is 7.05 and after the update it is 7.10. The newer font no longer contains a DSIG (optional digital signature table) there are also changes in the CMAP table.

If you manually install the old version 7.05 on a machine that has the Windows update the problem goes away. You can manually install the font by right clicking on the .ttf file while holding down shift and select "Install for all users". At least this fixes the problem in Firefox 38.0.6, you might need to restart the browser before it takes affect.

If you have a machine that doesn't have the Windows update and you install only the font of that Windows update (version 7.10) the problem also starts to occur there. It really seems to be the font update itself that causes the issue. Still interesting why it doesn't occur in the latest Firefox version though and what change in the font is causing this.

Hope this helps.

[Moonchild]

So I was correct then that the font got updated. How was it binary equivalent then?

As to why the font becomes italic, it's most likely what I indicated earlier: the font has a change that makes it considered invalid/corrupt (most likely rejected by our Open Type Sanitizer) and it falls back to the closest equivalent in the family which would be italics. Current Firefox probably has made changes to its OTS being more lenient allowing the font to pass. Finding a regression window on Mozilla's tree will probably point to what change caused this to start passing.

[Robbie]

The fonts I captured before and after the update are not binary equivalent. The Get-FileHash in PowerShell is different, also the file size is slightly different.

Hash for times.ttf version 7.05 F2CB777422A10368904D3F691E650E39DA862FE723389056324927DF540A35EC
Hash for times.ttf version 7.10 43B6511E032B2B6EBF4B62384B2FA81F7183D67E424BFFB711FA6E4BB21C954C

Indeed Firefox does a fall back for some reason.

[RealityRipple]

I see what happened; I still have a VM without KB5068861, so I checked it, and it has Times 7.10, and it does suffer from the italic issue. Instead, it has KB5067036 installed, which is the Preview Update (26200.7019), which also included the new font.

[Robbie]

A developer on my team looked into this issue in our fork of Firefox.

When the Mozilla engine loads the “Times New Roman” font family, the regular and bold variant is identified as TrueType, while the italic variants as OpenType. Mozilla uses NEWTEXTMETRIC flags to determine the font type: https://learn.microsoft.com/en-us/windows/win32/api/wingdi/ns-wingdi-newtextmetricw If the NTM_TT_OPENTYPE flag is present, the font type is detected as OpenType TrueType, which is superior to plain TrueType. The engine does not expect a family can consist of different font types, and removes the “low quality” ones from the list. The latest Firefox does not suffer from this problem, because the code has been removed in Firefox version 141 (see 1960146 - Remove GDI font backend), and according to the ticket was unused quite some time before the removal.

A possible fix would be to limit the removal to identical styles to allow mixed technology in a single font family in the Mozilla engine. Changing the way the font type is determined would probably be more dangerous.

Here is a link to the PR where we fixed it in our fork, maybe it is also useful for Pale Moon.

[jobbautista9]

Patch itself for convenience since BitBucket's frontend is broken in Pale Moon (requires PerformanceObserver and WeakRef, they both can be polyfilled as seen in their respective links however, with the former also being an opt-in feature in Pale Moon. You will have to deal with BitBucket's CSP though, which I personally just overrode to null with the moz-rewriter add-on): https://bitbucket.org/uplandsoftware/ob ... a725d6/raw

Code: Select all

From 9fdc998669e2a5bfae5d5f78771ee1ec9ba725d6 Mon Sep 17 00:00:00 2001
From: David Cernoch <dcernoch@uplandsoftware.com>
Date: Tue, 25 Nov 2025 16:25:20 +0100
Subject: [PATCH] SHARED-96874 Times New Roman always italic

- FIX: Restricted font technology optimization to the fonts with identical style.
---
 gfx/thebes/gfxGDIFontList.cpp | 18 +++++++++++-------
 1 file changed, 11 insertions(+), 7 deletions(-)

diff --git a/gfx/thebes/gfxGDIFontList.cpp b/gfx/thebes/gfxGDIFontList.cpp
index cce880b45..a9a45248c 100644
--- a/gfx/thebes/gfxGDIFontList.cpp
+++ b/gfx/thebes/gfxGDIFontList.cpp
@@ -447,13 +447,17 @@ GDIFontFamily::FamilyAddStylesProc(const ENUMLOGFONTEXW *lpelfe,
     GDIFontEntry *fe = nullptr;
     for (uint32_t i = 0; i < ff->mAvailableFonts.Length(); ++i) {
         fe = static_cast<GDIFontEntry*>(ff->mAvailableFonts[i].get());
-        if (feType > fe->mFontType) {
-            // if the new type is better than the old one, remove the old entries
-            ff->mAvailableFonts.RemoveElementAt(i);
-            --i;
-        } else if (feType < fe->mFontType) {
-            // otherwise if the new type is worse, skip it
-            return 1;
+        // XXXOL DC Changed: Only optimize font entries with same weight and italic (see SHARED-96874)
+        if (fe->mWeight == logFont.lfWeight &&
+            fe->mItalic == (logFont.lfItalic == 0xFF)) {
+            if (feType > fe->mFontType) {
+                // if the new type is better than the old one, remove the old entries
+                ff->mAvailableFonts.RemoveElementAt(i);
+                --i;
+            } else if (feType < fe->mFontType) {
+                // otherwise if the new type is worse, skip it
+                return 1;
+            }
         }
     }
 
-- 
2.51.0

[Robbie]

Microsoft released another preview Windows Update KB5070311 which installs a new version of the Times New Roman font, version 7.11. With that version the italic issue no longer occurs with Firefox 38.0.6.