There is a shadow under my glass block. light opacity is 0

So under my glass blocks there seems to be a shadow. The light opacity is 0, yet there still seems to be a shadow. I've tried setting it to 15, 0, and 255. All don't work. This only affects my modded glass blocks (they are translucent) and not the default MC glass blocks. This doesn't affect any of the glass panes. I've tried asking in the discord MCreator server. Someone suggested it may be a MCreator bug. Please help me with this. Thank you in advance.