[2.0.62] Opening map while in blueprint editor drops changes without warning

[sben]

When having a blueprint opened and editing it (having unsaved changes, e.g. added description and removed carefully selected buildings),
there is no warning about losing unconfirmed changes when opening the map (typing [M] or clicking on the map in the top right corner)

[Rseding91]

Thanks for the report. This is now fixed for the next release.