Minecraft wiki entry for Fishing, associated text: The maximum distance the player can get between the bobber and themselves is 33 blocks. Any further and the bobber and line detaches, returning to the rod.
If the players casts the bobber into a waterfall, the bobber floats up the waterfall until it reaches the top and remains there until the player either pulls it back in or catches fish on the line. If a fish is caught on the line, the bobber then falls down the waterfall.
The player can catch fish even if occupying the same block space as the bobber.
The player can freely switch between fishing rods after casting the bobber, with the enchantments on the casting rod being preserved in the bobber. This means that one rod can hook an item and another can reel it in, and the durability cost is subtracted from the rod currently equipped.
The player can obtain the achievement 'Cow Tipper' from reeling in leather‌[BE only].
If the bobber is too close to the land, the small splashes, as well as the trail of particles heading toward the bobber, can be seen on the land.
The player can fish while using the fishing rod in the off-hand slot.‌[JE only]
When in third person mode, the fishing rod is hidden, but the line and bobber are still shown.