1 files changed, 34 insertions, 0 deletions
diff --git a/mail/thunderbird/files/patch-bug1504834_comment10 b/mail/thunderbird/files/patch-bug1504834_comment10
new file mode 100644
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+++ b/mail/thunderbird/files/patch-bug1504834_comment10
@@ -0,0 +1,34 @@
+https://bugzilla.mozilla.org/show_bug.cgi?id=1504834#c10
+https://bug1504834.bmoattachments.org/attachment.cgi?id=9111147
+mozilla-bmo1504834-part4.patch
+
+# HG changeset patch
+# Parent  46ea866ca3acb8bb5e1709ceb799b9c94f591dec
+Problem description: Tab-titles that are too long to fit into a tab get faded out.
+                     On big endian this is broken and instead of fading out, the 
+                     tab gets white and the font transparent, leading to an unreadable
+                     tab-title
+Solution: This is not a real solution, but a hack. The real solution would have been
+          to byte-swap the correct buffer, but I could not find it.
+          So the next best thing is to deactivate the fading-effect. Now all tab-titles
+          are readable, albeit not as pretty to look at as they could be. 
+Side-effects: I have not yet found an unwanted side-effect.
+
+diff -r 46ea866ca3ac -r 6ef20eee3f8f gfx/2d/DrawTargetSkia.cpp
+--- gfx/2d/DrawTargetSkia.cpp	Tue Oct 22 12:27:22 2019 +0200
++++ gfx/2d/DrawTargetSkia.cpp	Thu Oct 31 09:11:56 2019 +0100
+@@ -1861,6 +1861,14 @@
+       SkCanvas::kPreserveLCDText_SaveLayerFlag |
+           (aCopyBackground ? SkCanvas::kInitWithPrevious_SaveLayerFlag : 0));
+ 
++#if MOZ_BIG_ENDIAN
++  // Pushing a layer where an aMask is defined produces wrong output.
++  // We _should_ endian swap the data, but I couldn't find a workable way to do so
++  // Therefore I deactivate those layers in the meantime.
++  // The result is: Tab-titles that are longer than the available space should be faded out.
++  //                The fading doesn't work, so we deactivate the fading-effect here.
++  if (!aMask)
++#endif
+   mCanvas->saveLayer(saveRec);
+ 
+   SetPermitSubpixelAA(aOpaque);