Maybe it's a bug and not a feature? Which makes me wonder, what if everyone just started bug-reporting this popup like at least once a week?

Honestly, just add all important things of the newest patch (including Pearl Shop offers if you must) to the loading screens (they already do this partly). This way we have no popups + more people are informed about things.

Put important news in the loading screens.  The PEN Blackstar ad has been there forever, and it can be replaced by more relevant info....

I hate having to get rid of that window every day.

I know it's bad practice to tack onto other peoples' suggestions, but I'm doing it anyway:

How about the little black/red BS pop-up that constantly wants you to know you have better gear than your Gathering Clothes or whatever else? All these swirls and flashes and pop-ups and red dots need to heck off. Keep the tiny little (X) number to indicate how many items are in my black spirit safe or challenge reward or available skills, sure. Get rid of all the other "LOOK HERE" crap.

Please implement the option to turn it off permanently or make it that it pops up when you first login each day. but everytime you swap character is really annoying. I´m sure players could live with that.

What do u mean????
Its all fine for me. I can even see my shadow

Ha!

Except for when the window in question pops up......

I agree 1000000%. This new popup News windows is anoying as hell. Not only does it popup ever damn day, it doesn't go away the first time I click the "Don't show again" message. I have to click it several times before it finally goes away. This window need to go die in a fire.