diff --git a/editor/ui/composer.js b/editor/ui/composer.js
index 30104f6fae47..1850a9737920 100644
--- a/editor/ui/composer.js
+++ b/editor/ui/composer.js
@@ -172,3 +172,8 @@ pref("editor.last_background_color_picked", "255,255,255");
 pref("editor.new_cell_has_space", true);
 
 pref("editor.throbber.url","http://www.mozilla.org");
+
+pref("editor.maintain_table_structure", true);
+pref("editor.table_delete_key", 0);
+
+pref("editor.use_custom_default_colors", 1);
diff --git a/modules/libpref/src/init/all.js b/modules/libpref/src/init/all.js
index df46ce1203c8..d6f5a6187609 100644
--- a/modules/libpref/src/init/all.js
+++ b/modules/libpref/src/init/all.js
@@ -289,6 +289,7 @@ pref("intl.charset_menu.static",           "iso-8859-1");
 pref("intl.charset_menu.cache",            "");
 pref("intl.charset.detector",              "");
 
+pref("font.default", "serif");
 pref("font.size.variable.ar", 16);
 pref("font.size.fixed.ar", 13);
 
diff --git a/modules/libpref/src/init/editor.js b/modules/libpref/src/init/editor.js
index 30104f6fae47..1850a9737920 100644
--- a/modules/libpref/src/init/editor.js
+++ b/modules/libpref/src/init/editor.js
@@ -172,3 +172,8 @@ pref("editor.last_background_color_picked", "255,255,255");
 pref("editor.new_cell_has_space", true);
 
 pref("editor.throbber.url","http://www.mozilla.org");
+
+pref("editor.maintain_table_structure", true);
+pref("editor.table_delete_key", 0);
+
+pref("editor.use_custom_default_colors", 1);