Don't put tmux window in background

Some contributor made the decision to do this, which seems pretty silly
to me.

Author: tpope

autoload/rails.vim

@@ -848,7 +848,7 @@ function! s:app_background_script_command(cmd) dict abort
   elseif exists("$STY") && !has("gui_running") && screen && executable("screen")
     silent exe "!screen -ln -fn -t ".s:sub(s:sub(a:cmd,'\s.*',''),'^%(script|-rcommand)/','rails-').' '.cmd
   elseif exists("$TMUX") && !has("gui_running") && screen && executable("tmux")
-    silent exe '!tmux new-window -d -n "'.s:sub(s:sub(a:cmd,'\s.*',''),'^%(script|-rcommand)/','rails-').'" "'.cmd.'"'
+    silent exe '!tmux new-window -n "'.s:sub(s:sub(a:cmd,'\s.*',''),'^%(script|-rcommand)/','rails-').'" "'.cmd.'"'
   else
     exe "!".cmd
   endif