Selection for ExtractSelection not saved in state

[alwaysonemorebug]

The topic is a known bug and was discussed in the past, but I cannot get the proposed workaround to work.

Situation:
My pipeline is created by a Python script. To work on a subset of the data, I use QuerySelect followed by ExtractSelection, e. g.:

nmdSel = QuerySelect(QueryString='(nmd == 5)', FieldType='CELL', InsideOut=0)
extractSelectionNMD = ExtractSelection(registrationName='extractSelectionNMD', Input=transform1, Selection=nmdSel)

When I use the SaveState command, the QuerySelect part is not saved. When I load the saved state in a new session, the pipeline is broken because of the missing selection in ExtractSelection.

A potential solution is not working:
During the search for a solution, I found a post from 2020 where the use of SelectionQuerySource is proposed as a workaround. The post says to remove
QuerySelect(QueryString='id == 1', FieldType='CELL', InsideOut=0)
and to add

sqs = SelectionQuerySource( ProcessID=-1, QueryString='id==1', HierarchicalIndex=-1, FieldType='POINT', HierarchicalLevel=-1)
extractSelection1.Selection = sqs

Problem:
When I try to execute SelectionQuerySource with FieldType='POINT' (or with FieldType='CELL'), I’m getting an error message saying that SelectionQuerySource has no attribute FieldType. In the documentation of SelectionQuerySource, I see “field type” in the text and an attribute called FieldTypeOption, but no attribute FieldType. I tried some variations of the SelectionQuerySource command, but my knowledge of ParaView (and its data structures) is not sufficient to get it to work.

Is there a solution or workaround that allows to save a selection used for ExtractSelection in a saved state?
Why is FieldType='CELL' not working anymore for SelectionQuerySource?

I’m using ParaView 5.11.2 on Windows 11.

Additional information found during the search for a solution:

• Another example (from 2013) where FieldType='POINT' is used with SelectionQuerySource
• A Python code snippet allowing to save the state to a .py file. (The SaveState command “only” allows to save to a .pvsm file.) Doesn’t help, the selection is also missing in the .py file.
• A post and an issue of the possibly related topic of Find Data selections being missed by the trace recorder

[theodorebaltis]

Did you try the SelectPoints method as mentioned here?

[alwaysonemorebug]

Thanks for the suggestion.
Yes, I tried.
At a first attempt, both SelectPoints() and SelectCells() caused ParaView to crash at the line selection=SelectPoints(). Not even an error message, the ParaView window just disappears. This seems unusual, I’ve not seen that before. I could try to narrow it down by simplifying my pipeline and see if the switch from QuerySelect(..., FieldType='CELL', ...) to SelectCells makes a difference.
Do you have any other example showing the use of SelectPoints and SelectCells? I struggle to understand the code posted by Jean M. Favre on Oct. 1, 2018. According to the documentation of SelectPoints, the only arguments of SelectPoints() are query and proxy. But the post suggests to define FieldType and QueryString after SelectPoints. selection=SelectPoint() defines that points shall be selected. I don’t get the point () of selection.FieldType='POINT' two lines later in that post.