If front window may be swung out and left side window slid back it might allow driver to wrap something around the cab support post. This might explain the post being obscured by the yellow thing at the bottom. Mebbe driver was being whimsical and put a stuffed toy there?
Also noticed that there is a hand-hold presumably for mechanics to climb up to the engine compartment. For some buses this hand-hold is chrome silver yet on other buses it has been painted red. The Q bus variant appears silvery, ie not painted red. While a silver handle could have been painted red in a refurb, mebbe anons could use this to discriminate between some bus pics.