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lhillman, Thanks! I've had this problem for months, with the customize button working only sporadically. The workaround you have found seems to have fixed it for me.
The issue here is, that the windows game bar is blocking the mouse button input somehow (though it is not displayed while in fullscreen mode).
This not only happens to the weather customize button (which just happens to be at the same high as the game bar), but can also be tested by moving the in-game popup of the GPS to the right of the screen. Suddenly, the buttons under the (invisible) game bar will not work. If you move the GPS a bit up or down, the button will work again (but some other button might not).
I made a screenshot of it to show the issue. This should be fixable by the devs.
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