fix(firefox): copy the wallpaper, Firefox won't follow the link

The darknix.png symlink out of the profile left the new tab blank, even
after a restart: Firefox's sandbox does not follow it. udt-accent now
copies the wallpaper over the slot on every change instead, removing any
leftover link first so the copy cannot write through it into the
wallpaper. install.sh no longer makes the link.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

1 files changed, 19 insertions, 0 deletions

diff --git a/bin/udt-accent b/bin/udt-accent
index 69698d1..2dfc9a0 100755
--- a/bin/udt-accent
+++ b/bin/udt-accent
@@ -19,6 +19,7 @@ import json
 import math
 import os
 import re
+import shutil
 import subprocess
 import sys
 import tempfile
@@ -63,6 +64,8 @@ PALETTE_RASI = Path.home() / ".config" / "rofi" / "udt" / "palette.rasi"
 # install.sh symlinks ~/.cache/wal/colors.json here, so the real file lives
 # with the rest of the palette and ~/.cache/wal holds nothing but that link.
 COLORS_JSON = CACHE / "colors.json"
+# FF Ultima's new tab background slots. darknix.png is the one udt fills.
+FIREFOX_WALLS = "chrome/theme/color-schemes/walls"
 
 # The SDDM theme's live palette. ~/.cache is 0700 and unreachable to the sddm
 # user, ~/.local/share is 0755, so the file has to live here. Root symlinks
@@ -387,6 +390,21 @@ def write_colors_json(name, image):
     subprocess.run(["pywalfox", "update"], capture_output=True, check=False)
 
 
+def write_firefox(image):
+    """Copy the wallpaper into FF Ultima's darknix.png new tab slot.
+
+    A copy, not a link: Firefox's sandbox refuses to follow a symlink out of
+    the profile, and the new tab shows nothing. Every profile without FF
+    Ultima is skipped.
+    """
+    for walls in (Path.home() / ".mozilla" / "firefox").glob(f"*/{FIREFOX_WALLS}"):
+        dest = walls / "darknix.png"
+        # A leftover link would make copyfile write through it into the
+        # wallpaper itself.
+        dest.unlink(missing_ok=True)
+        shutil.copyfile(image, dest)
+
+
 def rewrite(path, pattern, value):
     """Replace group 1's tail in the first line matching pattern with value.
 
@@ -541,6 +559,7 @@ def main(image):
     write_sublime(name)
     write_sddm(name, image)
     write_colors_json(name, image)
+    write_firefox(image)
     # Before the helpers below start, which build and stage these two.
     write_grub(name)
     write_homepage(name)