Are you saying that this worked on the past or that you are expecting this from the new strict routing option?

Maybe irrelevant, maybe relevant.
Is there some article or guide about the behaviour of urls between joomla 3 joomla 4 joomla 5 , 5.2?
I believe a reason for keeping many sites to 3 or even to 4 is because of the not so clear transition to the urls.
I don't mean it is something that has become worse i am sure about the opposite.
It is just me and probably other webmasters have a problem figuring out if needed and when should make all kinds of redirects so as not not lose their seos.
For example a url copied pasted from joomla 3 with ids works when in joomla 4? and what happen to joomla 5? IDOes something changes in 5.2?
SOrry if you think i hijacked but i think it was a good oppurtunity as to define what it is to be expected.

URLs with modern routing in J3 will be identical in J4. URLs without modern routing in J3 will be identical in J4 as long as there isn't more than one level of categories after the part of the menu item. URLs in J4 and J5 are identical.

Are you saying that this worked on the past or that you are expecting this from the new strict routing option?

I expect that Strict Routing will also have an option to redirect articles/categories that were previously published with an ID in the URL to a version without an ID in the URL.

some third-party SEF components for Joomla 3 supported this, but when I migrated to Joomla 5, I found that many older SEF components were not migrated to Joomla 5.

@Hackwar the current settings of SEF in Joomla 5 for me now look like help with eliminating only 50% of duplicate URLs, but the remaining 50% of duplicate URLs are still available.

my site has thousands of articles that look like site.com/category/11-article or site.com/24-category/11-article and if i enable Remove IDs from URLs all those thousands of URLs will fail with 404 error instead of redirecting to the version of the page without ID.

so that @joomla completely eliminates all duplicate URLs there should be 2 additional settings:

1. redirect URL with ID to URL without ID
2. canonical links for pagination pages (for URLs like site.com/?start=10)

We did not claim that strict routing will fix all issues and solve all site setups. The current changes don't support what you are asking for. To be a bit blunt: if your site has IDs enabled, then didn't disable them, at least not now. This isn't a bug, but a feature request.

We did not claim that strict routing will fix all issues and solve all site setups. The current changes don't support what you are asking for. To be a bit blunt: if your site has IDs enabled, then didn't disable them, at least not now. This isn't a bug, but a feature request.

Thanks for the explanation!
I hope that in future versions of @joomla there will be an option to remove all duplicate URLs.

This isn't a bug, but a feature request.

@Hackwar I created a feature request: #44310