Key changes are not updated in selected part(s)

I rewrite the work that contains more staffs for singers and instrumentalists. Due to the easier intake of the text, at one point I separated the singing section into a special part. This is how I save written and this part in the second tab opens when new loading.

In the work the keys / key signatures are changed several times. Now I noticed that the changes to the keys in the main score was not automatically entered in the separated part. It would be good for this to be automatically updated.

If I newly select part now, all the changes of keys are correctly presented. If the keys changes are not updated automatically, it means that I would have to select parts again each time to have the correct changes in the key.