--- a/mail/app/profile/all-thunderbird.js
+++ b/mail/app/profile/all-thunderbird.js
@@ -492,17 +492,21 @@ pref("mail.tabs.closeWindowWithLastTab",
 // Where to show tab close buttons:
 // 0 - active tab only
 // 1 - all tabs until tabClipWidth is reached, then active tab only
 // 2 - no close buttons
 // 3 - at the end of the tabstrip
 pref("mail.tabs.closeButtons", 1);
 
 // Allow the tabs to be in the titlebar on supported systems
+#ifdef UNIX_BUT_NOT_MAC
+pref("mail.tabs.drawInTitlebar", false);
+#else
 pref("mail.tabs.drawInTitlebar", true);
+#endif
 
 // The breakpad report server to link to in about:crashes
 pref("breakpad.reportURL", "https://crash-stats.mozilla.com/report/index/");
 
 // OS Integrated Search and Indexing
 #ifdef XP_WIN
 pref("mail.winsearch.enable", false);
 pref("mail.winsearch.firstRunDone", false);