There is actually a sub forum here for the Offline Survey App. JS should work with Offline Surveys, if this specific case also works I cite Tpartner: "No Clue".
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Provide your LS version and where it is installed (own server, uni/employer, SaaS hosting, etc.).
Always provide a LSS file (not LSQ or LSG).
Note: I answer at this forum in my spare time, I'm not a LimeSurvey GmbH employee.