Closing this task as FY25-26 has ended and the WE1.9 KR that housed much of this work has been accepted. One note: I don't include the work by Anbar for WE1.9 here around affiliates + mobile onboarding because this task is specifically about Research-team contributions, but it was quite important to the WE1.9 report as well.

Quick summary of the WE1.9 report (internal doc) with a focus on the research side of things (as opposed to specific product recommendations). I'll try to put out an extended version of this on Meta in the weeks to come as well.

• Editing starts with reading: even as newcomers take breaks from editing, they continue reading and can notice tasks they might do when they're ready to edit again. Successful newcomers often have some sort of system for tracking these lists of TODOs, which keep one in the editing mindset and make re-entry to editing easier.
• Most newcomers receive very little feedback about their editing: most edits don't trigger any follow-up actions (or if they do, it's negative like a revert). This can generate a lot of uncertainty for newcomers who aren't confident that they are doing the right thing. A corollary to this is that folks like looking at their activity logs (probably more so than summary statistics, at least for newcomers) -- i.e. it's nice to see what you've accomplished.
• Specificity is key to personalization: intrinsic motivation that a particular concept is important (by oneself caring about it / reading about it) is key to completing edits / long-term motivation and removes the importance of extrinsic factors like e.g., pageviews to a page. This can often translate into editing on niche topics as well, which is generally easier for newcomers (often less-developed articles mixed with greater confidence from the newcomer that they can make a change).
• Still lots of missed opportunities around mentorship: editors are hesitant to reach out to their mentors or don't see the module on their Homepage; mentee questions can be repetitive or lack details. This sort of peer support is important though newcomers often turn to off-wiki supports -- e.g., chatbots, external search.
• Newcomers like that Wikipedia is not like social media: the human aspect of Wikipedia is much appreciated along with the autonomy to chart your own course and not be overly guided by opaque algorithms.
• Mimicry is key to learning how to edit: successful newcomers often turn to mimicking other content to learn how to edit -- e.g., copying structure from similar articles for drafting new ones, copy-and-pasting wikitext syntax for references but updating with new information.
• Free time remains a major barrier for contribution: free time is both a major barrier to editing and also an opportunity (when it opens up, that's often when engagement picks up).

Potential follow-up research right now will likely focus on Personalization and better understanding that space. We will also look for opportunities to continue work around Feedback/Mentorship as another major area where research would continue to be valuable.