Funnily, the good old action=render works well. :)
https://meta.wikimedia.org/wiki/Community_Engagement?action=render
https://meta.wikimedia.org/wiki/Volunteer_Supporters_Network?action=render

I could have sworn there was a ticket open for this... The underlying issue is in TextExtracts so tagging appropriately.

As mentioned yesterday we'll need to do some digging to work out where the problem lies here before committing to work. Right now it's not known which layer this issue happens, why it happens and whether it's trivial to fix or there is a bigger problem at hand here. This impacts meta.wiki and mediawiki

What's the easiest way to get the <translate> tag working locally? If I can do this I am happy to try and isolate the issue here..

Change 360984 had a related patch set uploaded (by Jdlrobson; owner: Jdlrobson):
[mediawiki/extensions/TextExtracts@master] Test for T167852

https://gerrit.wikimedia.org/r/360984

After some investigation, I think is well defined and believe this is ready. Moving to upcoming. cc @phuedx @ovasileva

@Jdlrobson: I've got two additional observations:

1. RESTBase, which PP is fetching previews from in this case, doesn't set the explaintext parameter: https://github.com/wikimedia/restbase/blob/b33bf906/v1/summary.yaml#L113-L126
2. I can't reproduce this issue on-wiki with and without the explaintext parameter set:
   • https://meta.wikimedia.org/wiki/Special:ApiSandbox#action=query&format=json&prop=extracts&titles=Technical_Collaboration&exsentences=5&exintro=1
   • https://meta.wikimedia.org/wiki/Special:ApiSandbox#action=query&format=json&prop=extracts&titles=Technical_Collaboration&exsentences=5&exintro=1&explaintext=1

RESTBase, which PP is fetching previews from in this case, doesn't set the explaintext parameter:

The explaintext isn't the problem here.
explaintext return extracts as plain text instead of limited HTML.
Limited HTML has a similar problem which is inherited by not being aware of the translate tags existence. When parsed it things it has plain text. T107206 may be related to this problem?

1. I can't reproduce this issue on-wiki with and without the explaintext parameter set:

That's because you are using the wrong page. I've updated the description but it's Community_Engagement that you should be requesting the extract from.

In T167852#3375357, @Jdlrobson wrote:

That's because you are using the wrong page. I've updated the description but it's Community_Engagement that you should be requesting the extract from.

Mibad. That's why I mentioned the explaintext parameter.

It should flatten translate tags

After looking at the API response, is that what the problem is here? Will flattening translate tags fix the following, which appears in the HTML and plain text extract from the example in the description?

[[&lt;tvar|wmf&gt;Special:MyLanguage/Wikimedia Foundation&lt;/&gt;|Wikimedia Foundation]]

After some more debuggin, this is just one way of solving it.
The fundamental issue if we go up a level is this: T168743

Then let's fix the fundamental issue… Thanks for getting to the root of the issue, @Jdlrobson!

Our estimations were a bit all over the place 3,3,5,8,coffee
The code is a little scary and in multiple places.
3's felt like we were doing this for other tags

We feel like we should not workaround this issue as this is going to bite us later when we actually want to localise these messages.
Olga pointed out that the links in the description are working now.. did something change?

Is there a way we can test this on the beta cluster? Currently templates are showing up within article text, so no way to know.

In T167852#3386333, @ovasileva wrote:

Is there a way we can test this on the beta cluster? Currently templates are showing up within article text, so no way to know.

No. The Beta Cluster is a wiki farm – a single server hosting multiple wikis – with each wiki corresponding to a different language. Installing the Translate extension on the Beta Cluster doesn't make much sense. We should probably do this on the staging server with the main wiki being multilingual.

Change 360984 abandoned by Jdlrobson:
Test for T167852

https://gerrit.wikimedia.org/r/360984

Can be signed off next train (Wed 5th) on mediawiki. You may need to edit the page to force a flush of the existing HTML.

I think we also need to take the time to document the behavior on-wiki. I'll add a pre-signoff AC.

Sign off is blocked till 12th. No train this week.

@phuedx hey not sure what you have in mind about updating docs.

• This relates to TextExtracts or Translate extension so should probably be documented there... not on Popups
• Not 100% sure what you want to document here. That it will not be translated?

Note: We can actually sign this tomorrow or Wednesday (train is 19:00–21:00 UTC Tuesday).

In T167852#3423423, @Jdlrobson wrote:

@phuedx hey not sure what you have in mind about updating docs.

• This relates to TextExtracts or Translate extension so should probably be documented there... not on Popups

But it does directly affect the behavior of Popups as it should now only display previews in the content language of the page regardless of whether the Translate extension is used.

I say should because…

• Not 100% sure what you want to document here. That it will not be translated?

Is that accurate? AFAICT any balanced translate parser tags in the extract will be translated whereas imbalanced ones won't. Am I understanding the changes correctly?

I've tweaked the wording a little to clarify that we're requesting previews in the content language of the page (?uselang=content). Thanks, @Jdlrobson!

In T167852#3428194, @Jdlrobson wrote:

We'll need to wait till tomorrow for the meta fix.

TextExtracts also caches extracts in memcached with a TTL of wgParserCacheExpiryTime. We'll have to wait for pages to either be touched or fall out of the TextExtracts cache naturally.