Not sure if this is a regression or not. Unless the XPath queries have changed dramatically during refactoring, I don't think that we've been normalising whitespace when searching for paragraphs with content before the infobox, i.e. it's the "\n" character and not the class that's breaking the transform /cc @pmiazga.

AIUI the following HTML should also break the transform:

<p> </p><p></p>…<table class="infobox"></table><p>foo</p>

I agree that this is an edge case has been lurking for some time. It's a regression in the sense that something has changed to make this a much more prominent edge case than before.

Change 448060 had a related patch set uploaded (by Pmiazga; owner: Pmiazga):
[mediawiki/extensions/MobileFrontend@master] Threat p nodes with mw-empty-elt as empty paragraphs

https://gerrit.wikimedia.org/r/448060

Added Technical-Debt as this patches FIXME: Make Special:MobileContributions use ContribsPager ASAP. that was added two years ago

Ok, reverting the tech-deb label, wrong task :(

Change 448060 merged by Pmiazga:
[mediawiki/extensions/MobileFrontend@master] Treat p nodes with mw-empty-elt as empty paragraphs

https://gerrit.wikimedia.org/r/448060

👍

@Jdlrobson: Tested the fix on the articles mentioned under QA steps in staging environment. As for checking it on some random articles, on staging I am finding it difficult to find one with lead paragraph/infobox in it. Is it on Beta cluster yet? I could then search for some more random articles and check on those.

Looks good on staging across a bunch of browsers

Chrome

Firefox

Safari

Opera

@ABorbaWMF: Just wanted to mention that this seems to be not working on Beta cluster yet, some of the articles on Beta still has infobox as the first thing instead of the lead paragraph. So, I don't know if the fix has landed on Beta yet, but I was going to mark it as "Done" after verifying it on all other environments. Do you move tasks to Done column as soon as it's working on staging or when it is verified on all environments? Also, if/when you do verify tasks in other environments, how do you usually keep track of which environments it's been tested on?

@Ryasmeen, @ABorbaWMF - thank you for testing! I also looked on production and it seems to be working there. @Ryasmeen - do you have a link to one of the articles that wasn't working on beta? Maybe we've stumbled across a separate bug...

@ovasileva: Sure, check these two articles for instance: https://en.m.wikipedia.beta.wmflabs.org/wiki/Bear or https://en.m.wikipedia.beta.wmflabs.org/wiki/Bearded_seal

Interestingly, on production the same articles have lead paragraph preceding the infobox but not on Beta cluster.

On Beta:

On en.wiki:

Sorry if we have and I've missed the comment but have we determined that the spike that @Jdlrobson previously observed (see below) has flattened out?

While doing chores, I noticed a spike in first interactive time for the Barack Obama page
Investigating it in wpt (there were no active campaigns) it became quite obvious
http://wpt.wmftest.org/video/compare.php?tests=180710_NX_JK,180704_JD_HN

This change would have gone live on the 2nd August (1.32.0-wmf.15) on English Wikipedia

Sure enough, the graph tells the story that this was fixed:

Thanks for checking!