The order used to sort scope keys etc., i.e.
https://wicg.github.io/import-maps/#longer-or-code-unit-less-than

if a’s length is greater than b’s length, or if a is code unit less than b.

is not a total order. For example,

• "A" is longer-or-code-unit-less-than "AAA"
• "AAA" is longer-or-code-unit-less-than "A"

Probably this should be something like

if a’s length is greater than b’s length, or if a’s length is equal to b’s length and a is code unit less than b.

or simply

if b is code unit less than a.

Probably the latter one is better, because it's simple to understand and implement.
I'll create a PR shortly.

(Memo: code unit less than also seems to have a spec bug)