hello

can you tell me please the purpose of this scheme that appears when inkscape starts:



also, how do i disable it?

thanks

That's the Page Border and Page Border Shadow.
The page border is important, because depending on the intended use of your image, only those portions of the image that fall inside the page border, will be visible. Now, that does NOT mean that removing the border will change this behavior. When you remove the border, it just makes the border not visible.

The shadow, imho, is useless. It's literally a shadow of the page border, and I cannot think of any purpose it might serve.

You can get rid of them 2 ways. One is to do it after you open a document, from Document Properties > Page tab, at the bottom of the window. The other way is to create a customized default.svg page, so that every time you open a new blank doc, it lacks the border and shadow. I wrote instructions at the end of this topic: viewtopic.php?f=6&t=162