General Question External MFDs "lock" button

[IL2windhawk]

In the top right corner of External MFD windows (near the 'close' button), there is a small button with a thumb-tack on in. The manual says this is the "lock" button, but there's no description. For the life of me, I cannot figure out what this button does. I know it doesn't prevent me from moving the MFD.

Thanks.

 

[Wishbone]

It locks the MFD to the vessel it was first opened for. You switch focus, and unlocked MFDs change displayed vessel, locked ones do not.

 

[IL2windhawk]

Got it. Thanks!