Merge in wrong direction deletes all custom fields

[disciple]

if a user merges a ticket into a wrong direction, the custom fields are getting fully deleted.
No prior question, no "are your sure, that ..." nothing.

wrong direction is in our case mostly: older ticket gets merged into newer ticket

It would be great if I could configure a prior check on the custom fields. If they may get deleted, to show the user the cause.
Especially if you are having tons of custom fields, it is very annoying to redo the work

are there any options to configure the behaviour of merging?

[lis9]

Did you set Ticket::MergeDynamicFields setting before?

Best regards
Daniel Lisiecki