The Collection extension has been generating multiple production errors for over a year. Some of the extension's functionality has been extracted into the Proton service. The book creation aspect of this extension however has not.
Number, severity, and age of known and confirmed security issues
See https://phabricator.wikimedia.org/maniphest/query/xa3bDF3ygt2r/#R for those who have access to Security issues
Was it a cause of production outages or incidents? List them.
Does it have sufficient hardware resources for now and the near future (to take into account expected usage growth)?
Is it a frequent cause of monitoring alerts that need action, and are they addressed timely and appropriately?
When it was first deployed to Wikimedia production
2008 or earlier, according to https://www.mediawiki.org/w/index.php?title=Extension%3ACollection&type=revision&diff=221705&oldid=217405
Usage statistics based on audience(s) served
Changes committed in last 1, 3, 6, and 12 months
Reliance on outdated platforms (e.g. operating systems)
Number of developers who committed code in the last 1, 3, 6, and 12 months
Number and age of open patches
Number and age of open bugs
Number of known dependencies?
Is there a replacement/alternative for the feature? Is there a plan for a replacement?
Submitter's recommendation (what do you propose be done?)