Errors migrating menu links

After all the effort that's gone into bug fixes for migrate, I'm re-running the migration I tried back in December to see how things fare. d6_menu_links is the only new issue I encountered and a number of others appear to be resolved.

I ran:
drush migrate-manifest manifest.yml --legacy-db-url=mysql://melissa:@localhost/tag1dev

d6_block
#2372785: Error running d6_block migration hasn't been resolved yet. Behavior was the same as before so I applied that patch.

d6_file
I didn't do any research or configuration for this one, so I'm not concerned that it didn't work. If it should, that would be nice to know, but I imagine research will turn that up.

d6_menu_links
This is the first new error I hit. Menu links had issues before, but the message is new. The migration failed with:

The ID menu_link_content:eebb7d12-0af3-4e33-ab01-1c41029352ca already[error]
exists as a plugin definition or is not valid
(/var/www/eight/drupal/core/lib/Drupal/Core/Entity/Sql/SqlContentEntityStorage.php:934)
Array index missing, extraction failed.  

First level menu items migrated, their children didn't. No further migrations ran, so I commented it out and continued. The rest completed of the migrations completed without error.

I still need to look at whether the data migrated as expected for remaining migrations, but there were no further errors.

Thanks for all the hard work on this! I've attached my manifest file in case it's useful and I'm happy to rerun this as needed.