Hi,
According to lava installation document ,I had installed lava-server to debian 9.5.0.Creating super user operation is ok(sudo lava-server manage createsuperuser --username $USERNAME --email=$EMAIL)  . But when using firefox browser to login in by created name , response message:
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    SRF verification failed. Request aborted.
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After configured browser to disable cookies,the response is still so.

Jiang Lao