Error messages like "Page not found" not documented

[quantoid]

We occasionally see Streamlit error messages pop up like this one:

Page not found The page that you have requested does not seem to exist. Running the app's main page.

This doesn't make sense to our app's users, and we can't find anything in the documentation about when this error would be reported. That makes it hard to explain to our users what went wrong, and even harder to do anything to avoid it in future.

[sfc-gh-dmatthews]

Thanks for the suggestion! I'm compiling a list of error messages to create a comprehensive troubleshooting section, so I'll be sure to add this.

[snehankekre]

This error should also be explained in the MPA guide.

[sfc-gh-dmatthews]

Since the user-facing error is currently documented as an image, I've added alt text to make sure it is discoverable by searching. We have new features coming out for multipage apps which will come with a lot of new content, but for this issue in the current state, making sure the current documentation will come up in search should address the issue.