Yesterday, we've observed the first degeneracy on ThomX cavity at ~115 kW stored. The shape of the stored power on the oscilloscope is really close to what has been published in the D-shape mirror's paper ("tek0000" transmission in yellow, piezoelectric activator in green, error signal in blue).
This mode could be a 8.0 or 9.0. 
We have also observed a change of the angle of the mode (the pictures "degenere", "degenere2" and "degenere3" were taken by order). The only changing parameters are the alignement and the length of the cavity. 
The last thing we noticed is the shape of the mode which could not be an hermite-gauss mode (Bessel mode ?).