Created attachment 152661 [details] the window with the error I have been using the TypoJTB extension, but since (I think) LO 6.2.4, there is an error message when I try to open the dialogue. It persists in 6.2.5. I am not quite sure if it's the extension's or LO's error, but I think this happened once and was repaired on LO's side…
Works for me in 6.3 RC2.