The question is whether we want to support this. Having a string on multiple lines is already supported via '|' for instance, so do we really need another way? Wouldn't it be good to re-read the spec and write a doc that explicitly list what we do support and what we don't want to support?

I could also live with not fixing this issue. Though in that case I suggest to provide a more meaningful exception message (something like what I suggested in#11911).

ping @symfony/deciders Any opinion on this?

If that is according to the yaml spec, we should support it as well. We removed support for other stuff like non-quoted strings starting with% to increase compatibility. That wouldn't make sense if the full spec is not supported anyway.

We don't want to support the full YAML spec but a subset of it. So, removing things that were not compatible with the YAML spec was needed but this is different from supporting features that are currently not supported.

👍 because this YAML feature is not that "edgy" and because the implementation is reasonably small and simple.

Status: reviewed

ok, let's do it. But that's a new feature then, which should be done on master.@xabbuh I let you merge this on master (there are some conflicts).

is there is any update of this fix ?
regards