Linuxcnc 2.9.x and Glade GTK3 display issue

Just upgraded to 2.9.x from 2.7.x i am in the process of recreating my glade window with gtk3. All worked good in 2.7.x and gtk2 but now with 2.9.x and gtk3 this code below in my ini file deletes the the box_vel_info but does not start the motion_control_test.ui
not sure what is going on. help is appreciated

EMBED_TAB_NAME = MOTION CONTROL
EMBED_TAB_LOCATION = box_vel_info
EMBED_TAB_COMMAND = gladevcp -x {XID} motion_control_test.ui

Please start linuxcnc from the command line and check the output there. 
You will see there the error that does stop your panel to be embedded.

Norbert

thank you for reply

error says:
**** GLADE VCP ERROR: with xml file: motion_control_gtk3_.ui : gi.repository.Gtk' object has no attribute 'glade'

bump

might help to post your 'motion_control_test.ui'

Here you go

Line 24, replace this:

with this:
works for me on 2.10:

 

Sorry got distracted over the holidays.

So I made your recommended change to the glade file and it did not work. see screenshot

any more suggestions?

thank you as always
 

Works for me as well with the change Aciera suggested.

Im struggling to understand why it works for both of you. I have 2 different machines and a laptop and it works on none of them. All 3 computers running 2.9.3.

You changed nothing but line 24 ?