The #!/ prefix is an old convention that reserves this prefix for dynamic state within web apps and gadgets. It is, for example, used at https://wikitech.wikimedia.org/wiki/Deployments#!/deploycal/current. This currently triggers the "This topic could not be found. It might have been deleted or moved." warning every time.
We could easily move away form this prefix, but that wouldn't help in this case since DT would still emit the same warning. In this case, I think this prefix might actually offer a way to handle this in a more scalable way that doesn't require DT to hardcode every gadget's dynamic hash in existence. While not impossible, this prefix might be acceptable to opt-out more generally from DT reporting its failed attempt to search the archive as an error.
I see that DT already ignores #/ for the same purpose. I suggest excluding #!/ as well.
Context:
- Popularised by AngularJS: https://docs.angularjs.org/tutorial/step_09
- Used by Google: https://groups.google.com/forum/#!forum/javascript-globalization
- Used by Twitter and Facebook: https://blog.danwebb.net/2011/5/28/it-is-about-the-hashbangs, https://stackoverflow.com/q/3009380/319266, https://artsy.github.io/blog/2012/06/25/replacing-hashbang-routes-with-pushstate/, https://stackoverflow.com/a/37540182/319266
Related: