(Also see T223927: [Bug] [object Object] appears in TalkOverlay for the same output in a different code base)

Additional note: In mobile mode, I also get the warning "The URL is too long, the maximum size is 2,000 characters". This doesn't appear in the desktop version.

It also seems counter-intuitive, given that one would most want a url shortener for longer urls! Especially since the query.wikidata.org creates such long ones.

https://gerrit.wikimedia.org/r/plugins/gitiles/mediawiki/extensions/UrlShortener/+/master/extension.json See the end of the file (line 137). Maybe this needs to be bumped up. It could b made configurable I guess.

I'd be happy to see it raised an order of magnitude. Is there a possible negative application or security risk that it is aiming to avoid?

What would the process be for deciding whether the character limit can be raised?

Good question. Adding @Legoktm for comments. (Please feel free to take yourself off and redirect us if you're not the right person for this.)

I join Thomas in wondering. In particular, a common use case where one would get very long and legitimate URLs is Wikidata queries. Those long URLs are the only way to persist a query.

See T228778: Show a friendly message when creation of short URL fails for another part of the task