I can't find TransactionHelper in the correponding capella plugin

Dear all,
I just can’t find the transactionHelper in the capella/common/helpers plugin as shown in the Nosuggestion and projectExpo attached pictures. I have tried with two different versions of
capella studio 1.4 and 1.3 but I still have the same problem.
It exists in the capella repository though (differentContent.png).
Can anyone please explain that.
Regards.
Soulimane

noSuggestion.PNG
projectExpo.PNG
differentContent.PNG
noSuggestion.PNG
projectExpo.PNG
differentContent.PNG

Copyright © Eclipse Capella, the Eclipse Capella logo, Eclipse and the Eclipse logo are Trademarks of The Eclipse Foundation.