Hello Everyone

I made an extension to perform union operation on each selected group, but I got a weird result.

For example, there are three selected groups of rectangles:

Example - Three Groups of Rectangles

After using the extension on them, only the first group gets converted into a union path, the rest get duplicated and they aren't in their original positions anymore:

Weird Result

The expected result should be three union paths:

Expected Result

Please find attached for the extension and the example file.

Is it possible to get the expected result using an extension? How could I fix the extension?