How to append a number to an ID inside an XSL file

Question

I have the following XSL file which will be repeated many times (in my case 4 times):

Answer 1

In case the provided XSLT part is e.g. in an loop, you can use position() to get an incremented value (the current position in the loop) and concat():

Update as suggested approach didn't work in the settings:

Two different kind of notations that should work are:

and

The content can just be added after the attribute:

Just created a Demo with both versions.