Can one kasher the glass lid of a stainless steel pot?
There are different opinions on this. Please see the following link where this issue was discussed. http://dinonline.org/2017/01/05/kashrut-of-glass-plates/.
With the lid of the pot, there is another consideration, that even for those sefardim who hold that glass doesn’t need kashering at all, however the lid of the pot usually has a metal rim and handle, which wold need kashering even according to those sefardim.