[OPEN] Sometimes a strange line appears and causes many bugs

Bug Report
Expected behavior
When I make the borders of a map and finalize them, I expect the mapped area to be fully colored and functional for moving troops when I test it.

Actual behavior
When I make some borders near what I assume is the equivalent of 3/4 of the map, in many of the areas I map adjacent to that area a strange vertical line appears and causes some of the adjacent countries to be bugged as shown in the following images:

(Borders made as it shows the map editor)



(Borders with the odd line when you test the map after made a new border or adding a city)



(As you can see, because of this strange vertical line I cannot move the troops, it behaves as if it were water or a no go area when in fact the border was already completely done.)



I tried to redo the border of the most bugged area (Anatolia: Marmara) by deleting the country and redoing the border, apparently that fixes the bug only in that country but the bug is still in the lower areas).



I dont think its a super bug but it is annoying to have to re do one by one borders because that odd line, and I think it's partly due to this strange error code I got when trying to delete the other bugged country



and also i think its related to this small graphic bug which i think all guys on atwar knows on both classic and new default maps:

(look at the line on India, almost no one sees it but if you do zoom on the are you clearly can see it)



(and in Kazakstan and Urals its most clear to see it:)



(The same thing happens on new map on the sames zones:)





Steps to reproduce the behavior:

1. Make a map with dimensions similar to those of the default map (10k horizontal pixels by more than 5300 vertical pixels).
2. Create borders and countries in approximately 3/4 of the horizontal length of the map.
3. Test the borders and you will see that strange line that ends up booming all adjacent countries.

Information:
Browser: Chrome

Browser version: 103.0.5060.66 (Build oficial) (64 bits)

OS: Windows

Any other relevant information:
I dont know if that happens only on Chrome or could posibly didn't happen on other browsers, but i strongly think is something in the code and specifically to approximately 3/4 of the horizontal length of the map.

Thank you for the detailed bug report. I'll look into it when I can. However, please don't put [OPEN] in the title before I've had a chance to look at it, that's supposed to be my own organizational system only. Thank you