sometimes the screen becomes as in the screenshot when in non-main view (i.e. trade routes, statistics screens, etc.)
after the bug occurs, returning to main view does not help
if the game is in full screen, alt-tab out and back again fixes this
if the game is in windowed full screen mode i found no workaround
EDIT: i at least figured out what this screen is, it's the background shown when switching from one of the statistics screens to the trade routes screen (and vice versa)
Thanks for this report @hundreAd1800 , and for being so comprehensive with it! I've reported this to our teams now. Thanks also to @Asterix201252 for sharing your insights.
@hundreAd1800 , can you make sure you've done the usual steps from the troubleshooting guide - particularly verifying your files, making sure Windows and your graphics drivers are updated, and running with admin rights? Then, if it happens again, let me know. It'd also be really useful to know what activities you were doing in the game at the time, to try to narrow down when this happens. Thanks!
Hey guys and thanks for getting back to us with more information 
The dev team got back to us asking for the following details in order to expand their investigation:
@blendmode Thank you for getting back to me with the necessary information! I have just forwarded that to the dev team to help their investigation of the issue. Should they need more information, I will get back to you
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