It turns out that service workers are blocked in CTS because they are written as ES modules. This is a terrific thing, except we don't support, at least until bug 1360870 is resolved. I'm going to move the scope of test coverage for service workers to bug 1938663. Will rename this bug accordingly.
Bug 1904364 Comment 12 Edit History
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It turns out that service workers are blocked in CTS because they are written as ES modules. This is a terrific thing, except we don't support those in service workers, at least until bug 1360870 is resolved. I'm going to move the scope of test coverage for service workers to bug 1938663. Will rename this bug accordingly.