Layer Thumbnail Problem

I am not sure if this is the same issue, but I've never seen this before and it's a problem for me. Suddenly the thumbnail is bounding to the element in the layer and not the layer as a whole. I can there no longer see each layer element in context due to the thumbnail

Without knowledge of what you layer content are we can not tell if the thumbnails are correct or not correct. We have not idea how you have the Palette's panel options set.  Many of your layer contain lots of transparency. When most or a  layer bounds are empty of content you can not expect much from] the Layers Palette layer thumbnails.  I also have the thumbnail set to entire document so I have a idea where layer content fit within the documents composite.  You seem to use Layers bounds and content within your layers bounds seem sparse. The checkerboard in the first three layers are larger thee the ones in  other thumb. The also look soft like they may be screen captures the have been resized.  May actually be gray and white pixels not empty.  It would have been helpful it the turned on the visibility of layers and included the composite image in your capture