Huh? External power supply for Tbolt display?

Context: I have a Thunderbolt Display and a Mac Mini 2012. Am considering a new Mac Mini but want to keep my TBD. Need adapter like this FF MDP TB1/2 to MM USBC TB2.

The guidance here and on the Apple Store site are unclearly written and uncoordinated.

On the Apple Store site, there is this statement: “ However, using this adapter with an Apple Thunderbolt Display requires a power source, because the display does not provide power through the adapter.” Meaning?

Is it “Continue to use the TBD’s built-in power cord to power the display bc TBD can’t pull power from the FF USBC/TB3 port through its MM TB/MDP connector”?