The title says it all; You can't empty water buckets into existing water. They don't empty if you have something in your offhand or not, right-clicking underwater blocks to empty the bucket only plays the bucket emptying noise.
Coincidentally, this sometimes causes a bug in which the bucket texture sometimes doesn't match the liquids it stores, if any. For example, an empty bucket will actually place water when right clicked with, and a water bucket will update to an empty texture when used.
Edit: To reproduce (Not reliable, seems to randomly do it when using a water bucket)
1. Right-click water source blocks many, many times.
2. Attempt to place water on dry land.
Linked issues
duplicates
Comments
violine1101
Thank you for your report!
We're actually already tracking this issue in MC-181499, so I resolved and linked this ticket as a duplicate.
If you would like to add a vote and any extra information to the main ticket it would be appreciated.
If you haven't already, you might like to make use of the search feature in the future to see if the issue has already been reported.
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