Neither point applies to the scheme being proposed in this topic as far as I can tell.
The scheme being discussed works across all browsers - as described in the OP.
Later we could extend that to also allow “safe:” URLs, but which would (in the example I gave) only work in the SAFE Network’s own SAFEbrowser - something I have suggested might be used exclusively with SAFEnetwork.
But that’s not part of this proposal - I just mooted it to show that the proposal leaves open the path to supporting “safe:” URLs in future. This would not require conversion from one format to another - the existing addons would continue to work (just not understand “safe:” URLs) and the SAFE browser would be able to support both formats simultaneously - but could make it simple to share one form or the other, defaulting to the universal form for greater compatibility.
Conversion would only be needed if we wanted to drop the support for an existing URL format, which would be of debatable value, at least until the point it was so out of date it was no longer an issue! 