diff --git a/book/source/diag/user_id_certification.png b/book/source/diag/user_id_certification.png
index bfa8c06..5f4c7e5 100644
Binary files a/book/source/diag/user_id_certification.png and b/book/source/diag/user_id_certification.png differ
diff --git a/book/source/diag/user_id_certification.svg b/book/source/diag/user_id_certification.svg
index c117885..582ea0f 100644
--- a/book/source/diag/user_id_certification.svg
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