brightsign and unity...HELP !!!

Hello, I developed a small application on Unity that I would like to run on brightsign. When I encode the project in WebGl, the unity WebGl window appears but my application does not launch …
Could you help me ?

https://www.brightsign.biz/digital-signage-products/XT-product-line/XT244

I posted a solution which worked for me here