Extension talk:UrlShortener

[SOLVED] MW 1.43 compatibility

Can anyone confirm? Thanks. Jonathan3 (talk) 22:18, 4 December 2025 (UTC)

Looks like the master branch's extension.json requires MW 1.46!

I guess if I download the REL1_43 branch for MW1.43 it will work :-) Jonathan3 (talk) 22:42, 4 December 2025 (UTC)

It did. Jonathan3 (talk) 14:38, 9 January 2026 (UTC)

"You can also use this alternative URL:"

This alternative has an underscore, e.g. domain.com/_xyz. The text is "urlshortener-shortened-url-alt".

Why does it offer this alternative URL, and how can I get it to stop doing this? Thanks. Jonathan3 (talk) 14:39, 9 January 2026 (UTC)

It shows the alternative because the canonical may contain certain characters that are not easily linkable (reserved characters, etc).

You cannot turn it off, but you can ignore it. – Ammarpad (talk) 09:06, 18 January 2026 (UTC)

That's odd. I thought that's what $wgUrlShortenerIdSet was for.

GOOD NEWS THOUGH! There is a happy medium between turning it off and ignoring it - it doesn't appear at all if you just blank MediaWiki:Urlshortener-shortened-url-alt.

Presumably it still creates the alternative URL but nobody needs to know about that. Jonathan3 (talk) 14:49, 18 January 2026 (UTC)

I thought the alt URL always contained Special:UrlRedirector, as a safer fallback or something. But that's not the case. What is the alternative URL for? The docs don't say anything. Sam Wilson 02:58, 19 January 2026 (UTC)

It just takes the same format of short.url/characters but instead is like this: short.url/_characters. And the characters are different, so it might be short.url/G and short.url/_c Jonathan3 (talk) 10:37, 19 January 2026 (UTC)

Consider the short code G3E$ and its alt form _mzo2.

If you’re logged in to X and go to https://x.com/compose/post?text=https://w.wiki/G3E$, you’ll see that only https://w.wiki/G3E is linked, the $ is dropped.

That breaks the canonical shortcode G3E$, and will generally (mis)lead you to a different destination or a 404.

The alternative form does not have this problem: https://x.com/compose/post?text=https://w.wiki/_mzo2 – Ammarpad (talk) 14:31, 19 January 2026 (UTC)

I was going to ask why on earth anyone would include the $ character within $wgUrlShortenerIdSet, but then noticed that it's common enough (see https://github.com/search?q=wgUrlShortenerIdSet&type=code) and that it's in the example at Extension:UrlShortener.

Was the alternative URL introduced to deal with the problem caused by the $ character in $wgUrlShortenerIdSet on those websites?

If so, then maybe that should be documented so that other people could be told that it's OK to blank the relevant message page to avoid confusion. Jonathan3 (talk) 14:44, 19 January 2026 (UTC)

Yes.

If you're setting up UrlShortner extension for the first time today, you can avoid the problem by removing the character(s) in $wgUrlShortenerIdSet. – Ammarpad (talk) 19:23, 19 January 2026 (UTC)

I was going to edit the content page to reflect your answer, but had a further look and it seems that the real reason was to have an alternative to "bad words" (T230685: "Provide an alternate mapping for bad words"), though I can see that it has the effect you describe. Jonathan3 (talk) 22:33, 19 January 2026 (UTC)

@Ammarpad @Samwilson I made a couple of changes to the content page, but feel free to improve on them! https://www.mediawiki.org/w/index.php?title=Extension%3AUrlShortener&diff=8161635&oldid=8087389 Jonathan3 (talk) 23:00, 19 January 2026 (UTC)

@Ammarpad and Jonathan3: Those updates look good! Thanks. And so is the rationale here that the alt is unlikely to generate a bad word at the same time that the main one does? And yeah, good point about dollar sign — I've added a note to the docs saying that it might be good to remove it at set-up time. Sam Wilson 00:56, 20 January 2026 (UTC)

Error when dot is in URL

It seems when the URL has a dot, instead of showing "short URL not found", it gives an error: w.wiki/a., like in this one. Arcstur (talk) 11:48, 2 February 2026 (UTC)