Dorico always justifies the final system

For some reason I am not able to prevent Dorico to justify the final system in all parts of one project.
In the attached picture is one example of one part, one can see that the final system is only 26,8 % full and though the “Only justify …” setting is set to 50% Dorico insists on justyfing the system.
BTW It doesn’t matter which value I set in the setting, the system is always justified to full length.
What could be the reason for this behaviour?

Please remind yourself of the contents of this post about how to ask for help with problems that are specific to a particular project.

Well I did not want to post a whole Musical!
I will try to shorten it to a specific part.

Here is the bass part of one flow. (775 KB)

I changed your “only justify final system” setting to 80% instead of 50%, and that worked.

Thanks very much for attaching your project. Without it I wouldn’t have been able to figure it out. Because you have multi-bar rests switched on, the final empty bar is being treated as a multi-bar rest, and we have a rule that we don’t allow the final system to be unjustified if it ends with a multi-bar rest.

Ah! I was using the full score, not the bass part. When I tried 80% on the bass part, indeed the justification did not work.

But it would be nice if the final bar were not treated as a multi-bar rest. If that’s not possible, could this please be considered as a request, if the final bar rest is only one bar?

@ Daniel
Thanks for the explanation.
As it is not possible to deactivate the multi-bar function for one bar, you add this as an additional reason to allow some more flexibility with multi-bar rests as I wrote in post 11 and 15 from this thread:

@ Stephen Taylor
Thanks for trying

What would be the best solution to get a short final system but let the multi-bar rests active as they are needed at the beginning?
Manually moving the system handle at the end of the system with ALT + Left Arrow is possible but it takes really very long to achieve this (about 300 or more ALT+Left arrow clicks!).
I tried to insert a space with shift X in this bar as an invisible item to feign that this is not an empty bar but it does not work.

I just discover that with CTRL + ALT + Left arrow the values are changing much faster, so shifting the system handle is indeed one possible way.
I still would like to know why adding a space with Shift X does not work.