Please help us help you and fill where relevant:
LimeSurvey version:  6.16.0+251120 upgraded from  6.6.8+241104
Own server or LimeSurvey Cloud: local linux server
Survey theme/template:
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After upgrading the server we have a systematic problem.
Create a new survey from 0, trying to save in any setting section something (survey menu, pubblication, etc etc), the first time i save the data i got an error, refreshing the page and saving again all work as intended (testing with different browser like chrome and firefox, clear cache and so on)
this is the error

Uncaught ReferenceError: validateSettingsForm is not defined    <anonymous> test-questionari.mimit.gov.it/index.php/...ings&surveyid=793336 line 1 > injectedScript:22    jQuery 7        dispatch        handle        trigger        trigger        each        each        trigger    run test-questionari.mimit.gov.it/tmp/assets...adminbasics.min.js:2     jQuery 10    a3f7 test-questionari.mimit.gov.it/tmp/assets...adminsidepanel.js:38     n test-questionari.mimit.gov.it/tmp/assets.../adminsidepanel.js:1     0 test-questionari.mimit.gov.it/tmp/assets.../adminsidepanel.js:1     n test-questionari.mimit.gov.it/tmp/assets.../adminsidepanel.js:1      test-questionari.mimit.gov.it/tmp/assets.../adminsidepanel.js:1      test-questionari.mimit.gov.it/tmp/assets.../adminsidepanel.js:1