diff --git a/conf/i3/config b/conf/i3/config
index b74f9d93..58f728f9 100644
--- a/conf/i3/config
+++ b/conf/i3/config
@@ -279,6 +279,9 @@ bindsym $mod+Shift+m exec audacious
 #for_window [title="^Mozilla Firefox$"] floating enable
 for_window [title="^Tor Browser$"] floating enable
 for_window [title="galculator"] floating enable
+# https://chrome.google.com/webstore/detail/sidewise-tree-style-tabs/biiammgklaefagjclmnlialkmaemifgo
+# use in undocked mode (in extension settings) with i3!
+for_window [title="Sidewise"] floating enable
 # insert new rules above this line
 # https://github.com/keybase/client/issues/8232
 for_window [title="tracker - .*"] floating enable