[pikevi]

A photo will be helpful.

What is the shape of the lesion? Have you noticed it growing bigger? Is it dry ( I assume it is since it is "paper thin and can see through")? Do you see the mesh of venules ( that may mean chlorophyll has been 'lost' or 'eaten')?

If it is dry and not getting bigger I don't think you have to remove it. If you do want to remove it you could trim it around the dry part of the lesion and not inflict damaged to the healthy cells.

Please wait for others' suggestions.

I the meantime I wonder if you could get a photo of it!?

Thanks.