diff --git a/changelog.d/5930.misc b/changelog.d/5930.misc
new file mode 100644
index 0000000000..81dcc10e6d
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+++ b/changelog.d/5930.misc
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+Add temporary flag to /versions in unstable_features to indicate this Synapse supports receiving id_access_token parameters on calls to identity server-proxying endpoints.
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