I replied you in the support thread you opened regarding this topic. I will, however, post my reply here as well, so it can be reviewed by the community.
I made a research whether this common behavior can be work around. Unfortunately, this would not be possible. The only solution that I can provide, is to keep the key used for multiple selection pressed while opening the ContextMenu. Thus, the control will perform a selection over the current task, but will not clear the previous ones as it will still perform a multiple selection.
If further assistance regarding this topic is needed, I would kindly ask you to continue our discussion in the support thread, so the communication is kept consistent.
Thank you in advance for understanding.
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