Environment and Climate Change Canada (ECCC) says in a written statement that “at this time, neither the substance nor its source has been identified. However, preliminary analysis at an ECCC laboratory suggests that the material could be plant-based.”
Looks like the touton jokes may have had it right: https://www.theweathernetwork.com/en/news/nature/outdoors/the-surprising-theory-behind-newfoundlands-mystery-blobs
This sounds like one more theory to me since the