@alzhao I try upload default firmwares for AR750 (2.?) and GL UI exist no problems. So is not really so possible that this is problem with how I am using web browser. Anythings is possible, and I am experienced but maybe I do somethings stupid, but at this moment everythings look like problem with firmwares.

I think next is locate manually GL UI files and try to manually direct browser. But if you have a suggestion I can do I will do also.