I'd like to create an extension, that does add a spareparts tab to products in the backend, similar to crossell, upsell and related products.
Seems a quite easy task with new dependency injection xml file, but I am not able to make it work. I already tried to debug via xdebug, but magento seems to not even enter my new block. Besides from this rewrite, the extension is loaded and working.
Any help appreciated.
Here is a gist, with the corresponding files:
Thanks a lot!