UV problem

[Maks AAA]

https://youtu.be/X9fiVUo1Rl4 youtube video of my problem for better understanding 

when I unwrap my mesh, why do the two halves of the UV islands connect together, preventing me from moving them separately? I can’t figure out why this is happening. I have already tried:
Enabling and changing Sticky Selection Mode
 Toggling Live Unwrap
Toggling UV Sync Selection

[Maks AAA]

and yes, i fixed it by manipulating vertices manually, but i want to know why this happened? 

[Martin Bergwerf]

Hi Maks,

Looks like a bug to me, but it happens because you have your Marging set to 0:

Which lets those Vertices be in the exact same Position in the UV Map and the UV Island Selection apparently can’t differentiate between the 2 and thus considers both Islands as 1, if that makes sense. This probably shouldn’t happen, but then again, you’re not supposed to set the Margin to 0 either😉

If you want, you can file a Bug Report and see what they say.

[Maks AAA]

yep, that helped, there is no way i would solve this without your advice, thanks!

[Author]

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