I have not played Stellaris for long so I apologize for the candid question...

But, whenever I try to reinforce my fleets, it kinda works ok if they are not moving while every new ship is built and "shipped" to rejoin the fleet.

But whenever I'm in a war, moving my fleets from planet to planet, and regularly pressing the "reinforce fleet" button to make for losses, I end up with countless micro fleets scattered across systems. The new ships won't always merge with their intended fleet automatically, if I move around a lot, they get scattered into side-fleets that I have to merge myself.

Do you know of a way to lock a newly produced ship to it's mother fleet, so that it will try relentlessly to find the fleet and merge with it ?