[0.18.40] Crash while closing blueprint library: BlueprintLibraryGui::BlueprintLibraryGui

[DFPercush]

tile section of map editor was open
blueprint library was open
clicked the x to close the blueprint library
a window behind it appeared to close instead, I don't recall which that was, but it wasn't my aim, I think the game closed the wrong window and then tried to reference it.
Not sure whether I tried clicking the x again after that.
a split second later the crash occurred

I was working with blueprints containing tiles from the mod Robot Zone. I believe I was in the middle of changing the icon for the blueprint and trying to save it, but I don't think that's what made it crash. I am using Editor Extensions as well, maybe that has something to do with it. But somehow, the wrong game window received the mouse event and closed, while the one I was trying to close stayed open. Log and dump attached. Thank you for your attention.

[kovarex]

Thanks for the report, it was fixed for the next release.