Solved in context of i.a. T28982. Now this is handled correctly and user can also configure the behavior.

I would say some code in Modules\IGT\IO has to be adapted to fix this bug. Possibly the class mitk::NavigationDataRecorderDeprecated, if it is still in use.

The output of the abovementioned command, for reference:

Discussion result: yes makes sens.

Started dicussion about it. Current discussion result: We should go for a new model view based implementation instead of try to fix the current boiler plate code.
Have to discuss design of the model view pattern in detail in the next MITK meeting.

The Fast Marching tool hast been removed with 2ef49f51d547. Also, no other tools exist that have a "Clear"-button.

in the new data structure it won't happen as there is no active label anymore. But you are right I thought the same when I looked through the class. My motiviation to refine this obsolete class was only limited 🙈 .

I can confirm the behavior.
I debugged a little bit and found the following:
The preview-image is an own data node (e.g. Threshold preview), stored in the data storage / shown in the data manager. The QmitkLabelSetWidget::OnVisibleButtonClicked-function only retrieves the current working image and sets its visible-state.

I just stumbled upon the following:

yes, that will help. Also, this worklist will be quite helpful, allowing a new form of "batch-processing".

The fix was updated and landed onto develop. I will close this now but the question remains in which scenario this datamanager-contextmenu entry / action could be relevant - I don't see any need for this.

In T29110, @kalali wrote:

• A newly created label is automatically selected?
  • Was mentioned in a checklist and should be checked, as this is relevant when it comes to using the label and observing the drawn mask color

Ok, I got it working as well. Thanks!
We can mark it resolved.

In T28808#238579, @a178n wrote:

I expect a circle in the cross-hairs, akin to Shape: cross or vertex. But there is None. Is this expected behaviour?

In T29141#238594, @kalali wrote:

Is this the same (T29110, see description point 3) and specifically T29110#235991?
If so, I have a fix for the > layer 0 problem which can be tested and reviewed in D632.

@gaoh maybe also the worklist feature covered by T29159 would also help/suffice? Than you could explicitly define the output path.

Now regarding the requested cosmetic change (requested by Fabian during the Hackathon) -
We use CTK checkable combo box to facilitate the selection of multiple options in a dropdown.
When all the options are selected by the user in the dropdown, the display in the dropdown automatically changes to "All".
This is done by a paint event of the Combobox where the string "All" is arbitrarily assigned. Ref: https://github.com/commontk/CTK/blob/c97620f43dec6b1eac894d7d9c491d2af236dc22/Libs/Widgets/ctkCheckableComboBox.cpp#L385
Thus, any custom text would require a change from CTK side.

The changes for the second part of the task are already incorporated in the 2022.04 release.

Yes. My work will take care of this. Just need to finish off the label merging for individual slices.