The bug
Throwing eggs and snowballs though cobweb just hits it and breaks. Shooting arrows and tridents through cobweb does not slow them down, they act as if they were being shot through the air.
Linked issues
Comments 14
Wouldn't an arrow slice through cobwebs though? I think this may be intended but we'll see what Mojang says.
Changed the behavior of all the throwable items to ignore none solid blocks (ie : Tall grass and such) and to get "stuck" when hitting a cobweb.
Can confirm.