Not all tests were updated in Bug 1739423 Any usage of the amazon mitm5 recording should be updated to use the mitm7 recording. https://searchfox.org/mozilla-central/search?q=mitm5-linux-firefox-amazon.manifest
Bug 1747810 Comment 0 Edit History
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Not all tests were updated in Bug 1739423 There are still tests referencing the manifest for mitm5 amazon recording, as well as other outdated recordings https://searchfox.org/mozilla-central/search?q=mitm5-linux-firefox-amazon.manifest