I built a canal to connect two lakes. I dug a trench and filled it in with 1 block deep water using a bucket until none of the water blocks were obviously flowing. However, the water still has "bubbles" above it, unlike normal lake water (as you can see in the screenshot below), and causes my player to move when I stand in it. When I ride a raft across this water, the raft jerks up and down, which seems like a bug.
I can make the water behave normally by applying a bucket to every single block, but this is kind of a pain, especially since it is impossible to tell exactly which blocks are producing the bubbles, so I have to fill in blocks that have already been filled in. I feel like water blocks that don't look as if they are flowing should not behave as if they are flowing.