I have checked SVG from Figma and Illustrator.
If the object standart, such as circle, triangle or square, then the additional vertex is not added. If the object has custom shape, then the additional vertex is added.
Please look the video.
I noticed that the vertex in which the path will be opened is duplicated.
Now I remove the duplicate manually in each shape.
Would be more comfortable if the vertex won’t be duplicated :)