Reproduction steps:

1. Place dispenser facing into an air block surrounded by solid blocks (see attachment)
2. Put any bucket of fish ("minecraft:cod_bucket", for instance) into the dispenser
3. Activate the dispenser with a redstone pulse
4. Stand near the dispenser and run the command:

   /say @e[distance=..5]
   

Expected: Water should form in the air block, and a fish (corresponding to the item used) should be spawned in the water.

Actual: Water forms, but no fish is spawned. The /say command verifies the fish to be absent, and not merely invisible client-side.

Notes: Tested both in vanilla and in a new, cleanly installed Spigot server (no plugins, newly generated world, etc) with operator privileges. Vanilla works as expected. Neither fish type nor dispenser orientation appear to make any difference.

Bug reports which do not 1) contain a declaration of testing in Vanilla 
and without plugins, or 2) in the case of plugin API bugs, contain a 
minimal reproduction case (source + jar please) will be closed. Bug 
reports must contain step by step instructions to reproduce the bug from a clean
 server install with no assumptions or prior knowledge. Also make sure 
you include the full output of /version in your report. Please copy and 
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