issue burndown chart gadget shows incorrect data when context selected

On a system dashboard I added GH Statistics burndown chart gadget. It is configured to show story points burndown for two defined contexts. Unfortunately it is uncapable of showing proper charts for contexts, it shows "default" context burndown instead.

Configuration:

• Custom field was introduced to specify which team is responsible for each issue. (field with simple selector: team A/ team B)
• Administrator created two filters, showing issues for each of the teams respectively. (filter consists only a custom field condition)
• Administrator shared those filters with all users.
• Two contexts were created based on those two filters.
• System dashboard was configured to show burndown chart statistics gadget (story points) for two contexts.

Problem:
The "Agile Charts" show correct data for each context (Agile -> Chart board -> Statistics burndown chart / story points) - see attached images.
The same information showed in system dashboard gadget is incorrectly presented - see attached image.

Maybe filter sharing makes charting gadget uncapable of resolving contexts propertly?