Water source blocks appear to be invisible underneath falling water. This issue can be seen when you let water drop on top of a source block, and you till the soil around the water source block. I've taken a screenshot in case you're not able to replicate it. Discovered this while creating a farm on top of another farm, and letting my middle water source block fall on top of one below it.
Thank you for your report!
However, this issue has been closed as a Duplicate of MC-126976.
It has been linked to this report. If you have additional information, please add it to the duplicated report.
Please search before reporting, as it's likely that one exists already.
Quick Links:
📓 Issue Guidelines – 💬 Community Support – 📧 Customer Support – 📖 Game Wiki