we have 3 test cases in /import-maps/* and they are all failing as expected TIMEOUT. I verified one locally on windows 10 and I found this in the UI:
assert_array_equals: expected property 0 to be "A" but got "log:A" (expected array ["A"] got ["log:A"])

@http://web-platform.test:8000/import-maps/acquire-import-maps-flag/worker-request/success.tentative.html:22:36
promise callback*@http://web-platform.test:8000/import-maps/acquire-import-maps-flag/worker-request/success.tentative.html:22:6
Test.prototype.step@http://web-platform.test:8000/resources/testharness.js:1958:25
promise_test/tests.promise_tests</<@http://web-platform.test:8000/resources/testharness.js:605:36
promise_test/tests.promise_tests<@http://web-platform.test:8000/resources/testharness.js:604:20
promise callback*promise_test@http://web-platform.test:8000/resources/testharness.js:603:51
@http://web-platform.test:8000/import-maps/acquire-import-maps-flag/worker-request/success.tentative.html:20:13

this looks like a mismatched type, maybe we are getting incorrect values?

:jgraham, can you take a look at this?

This seems to be something in WICG. Anne: do you know if this is a thing we are planning to support any time soon (I also think some of the tests here might be broken given there are failures in Chrome).

We're still evaluating the proposal in https://github.com/mozilla/standards-positions/issues/146. I think we're leaning towards positive, but it's not on any roadmap as far as I know.

:jgraham, should we move these tests to run as backlog?

Sounds like the right thing for now.

mark import-maps/acquire-import-maps-flag/ as backlog

https://hg.mozilla.org/mozilla-central/rev/73fe231fe26d