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+---
+layout: null
+permalink: /or/userchrome.html
+sitemap: false
+---
+
+http://ea5faa5po25cf7fb.onion/projects/tor/ticket/30812#comment:3
+
+More details: turns letterboxing dark, check the profile location in
+`about:profiles`, `cd` there, `mkdir chrome` and paste the below into
+`userChrome.css` there.
+
+```
+@namespace url("http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul");
+
+/* about:newtab and about:blank
+ * also remove white flash: see https://bugzilla.mozilla.org/1488384 */
+#browser vbox#appcontent tabbrowser,
+#content,
+#tabbrowser-tabpanels,
+browser[type=content-primary],
+browser[type=content] > html {
+	background: #2A2A2E !important
+}
+```
+
+Proof: https://onion.torproject.org/