Zoom in fully on a Cruiser.
When the ship dies wait until the shockwave begins.
Zoom out fully.
Witness a humongous shockwave!
Lower gamespeed to ensure you can move the camera in time.
Undocumented game feature 
Unless the shockwave damage also spread out that distance, which you dont seem to imply.
Undocumented game feature == bug? 
its a new feature added a couple of patches ago
The shockwave is, yes, but we’re talking about the graphics of the shockwave expanding outward if you zoom out from the exploding ship.
I don’t see a bug, there is always a big shockwave from a cruiser. This is intentional, or am I missing something?
The graphic effects of the shockwave from a cruiser blowing up usually travel a relatively short distance before disapating.
If youre zoomed in on the cruiser and zoom out at the exact moment the shockwave happens, it continues expanding right to the edge of the battlefield.
It’s a very minor graphic only glitch.
Aha, I see… this is indeed a bug, and you can expect it to be fixed