Change 301129 had a related patch set uploaded (by Jforrester):
Change default gallery mode to 'packed' on the English Wikipedia

https://gerrit.wikimedia.org/r/301129

Any updates on progress?

I believe this is close to being ready to be merged in. I'm tagging this with sprint 80 for Reading Web for Tracking, and will ask @Jdforrester-WMF if the merges can happen during that sprint.

Mentioned in SAL (#wikimedia-operations) [2016-10-26T23:18:01Z] <dereckson@tin> Synchronized wmf-config/InitialiseSettings-labs.php: Test setting gallery config differently on Beta Cluster enwiki (T141349, 1/2, no-op in prod) (duration: 00m 49s)

Mentioned in SAL (#wikimedia-operations) [2016-10-26T23:19:23Z] <dereckson@tin> Synchronized wmf-config/CommonSettings.php: Test setting gallery config differently on Beta Cluster enwiki (T141349, 2/2) (duration: 00m 45s)

Sorry for forgetting about this.

This change is now live on the Beta Cluster version of the English Wikipedia. See https://en.wikipedia.beta.wmflabs.org/wiki/Lion#Reproduction_and_life_cycle for an un-typed gallery that's now using mode=packed rather than mode=traditional, for instance.

If this is OK, please confirm, and then we can move ahead with deploying to production.

I don't see it working at that link? Is it turned back off?

In T141349#2747426, @AdamCuerden wrote:

I don't see it working at that link? Is it turned back off?

Comparison (old) version of the real article is https://en.wikipedia.org/w/index.php?title=Lion&oldid=651089584#Reproduction_and_life_cycle — and so:

Before
After

Any updates on this?
Can we move this to production?

Any updates?
What's blocking us doing this?
Who's planning to do this?

This is still lingering in beta configs. If it's a dead issue, I'd rather revert the beta changes than keep things out of sync for another 2 years. I don't see the difference in rendering, btw.