Thank you to Julien Rouhaud and Tender Wang for the reviews.
Julien's detailed guide has proven to be incredibly helpful, and I am
truly grateful for it.
Thank you so much for providing such valuable guidance!
I have initiated a new commitfest:
https://commitfest.postgresql.org/43/4346/
Furthermore, I have attached a patch that improves the code by moving
the initialization of "other_rels_list" outside the if branching.
Perhaps Tom Lane would be interested in reviewing this minor change as well?