Hi, my name is***** your mechanic automotive expert, and I will be happy to assist you today. I apologize for any delay.
Dear customer, to be honest, the space is too large for a support stick. There, what I recommend is that you install a rubber like the one that I am going to attach to you in the picture below.
With this rubber, you will be able to reduce the space between the roof and the window.
But, the truth, what I recommend you to get in contact with and upholsterer or body work garage, because they can simply attach a section of fabric in that area, and the truth is a fairly cheap job, I don't think they will charge you much for this, and it is the most feasible, so I assure you that it will be able to give you much more than a simple glue.
Also, and epoxy glue or a generic plastic rubber has no high cost and is sold by the meter, but I insist that attaching one more section of canvas fabric is a more reliable way because it is not glued, they will withstand you more than several days or weeks, because they withstand high temperatures under the sun.
Do you understand me, dear customer?
My goal is to give you the best advise i can, therefore please do not doubt to ask if you have any doubt or if there is anything else i can help you with.
Kind regards, Sebastian.