The spike in 115.0.2 specifically makes me strongly suspect something related to third-party modules.
Bug 1843977 Comment 3 Edit History
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The spike in 115.0.2 specifically makes me strongly suspect something related to third-party modules. Full changelog: https://hg.mozilla.org/releases/mozilla-esr115/pushloghtml?changeset=872b5aae170ffa755f89d0c6a9ebc380af677e9a