Please help us help you and fill where relevant:
Your LimeSurvey version: 6.1.8+230717
Own server or LimeSurvey hosting: Own server
Survey theme/template: Bay_of_Many
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The only admin theme included in this version is Sea Green. As a result, selecting any other theme breaks the site. Does anyone know where I can download the additional themes for version 6.x?

BTW, I have reported this bug . 

Thank you