Thank you for your question.
The door on the Tiger Americana stove opens to fill with fuel (wood or coal).
With the door open it is easy to clean the inside of the glass.
There are lots of stove glass cleaning products available but I just wait until the stove is cold, use a sheet of damp newspaper dipped in wood ash (Not Coal Ash) and rub gently, this takes any staining off the glass, then just rub dry with a dry sheet of newspaper.
Hope this helps?