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Changes between Initial Version and Version 1 of Ticket #33900, comment 8

initial	v1
9	9	Tangentially, the assumed `1` main network ID return value bothers me. A new default constant makes sense here, itself defaulted to `1` in WordPress core. And it can still be overridden in `sunrise.php` or `wp-config.php`. It's edge-case, but I've already needed to kludge this because a new network with a few sites took the place of the original one.
10	10
11		So for each of the 3 cases, I'd like for the `1` default return value to be configurable in some way.
	11	So for each of the 3 cases, I'd like for the `1` default return value to be configurable in some way. That could be handled in it's own ticket, too, since it's a separate initiative and could cascade into the default `$blog_id` too?