[6.0] Backport. Region map should respect saved center and zoom (#12883)

[thomasneirynck]

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• Have you followed the contributor guidelines?
• If submitting code, have you included unit tests that cover the changes?
• If submitting code, have you tested and built your code locally prior to submission with npm test && npm run build?
• If submitting code, is your pull request against master? Unless there is a good reason otherwise, we prefer pull requests against master and will backport as needed.

[thomasneirynck]

jenkins, test this