Can thief's open jail/any locked doors at all?

[Zols]

Title pretty much, tried googling this question and saw one answer saying they could open "grey/yellow" doors, but they may have been referring to another dragon quest game. (im well aware of the key for the red doors/and the magic key for blue doors and i know about the existence of the ultimate key, my question is can thief's open jail door's or other "grey" doors like the one locked door in the starting island after gaining a certain lvl).

Thank you for your time and have a good day.

[Lucas the Thief]

Jail doors are sadly ultimate key only

[Zols]

Sigh, suspected as much, thank you for the reply.

[GespenstKAF]

If you level up a Mage/Sage to the 30s, they learn Click, which I believe acts as a substitute for the Ultimate Key (in the NES version at least, to free up your limited inventory space)