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Your LimeSurvey version: 6.16.1
Own server or LimeSurvey hosting: hosting
Survey theme/template: fruity with some logo adjustments
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I have helped an organisation that wants to check whether their clients have the correct documents for a certain procedure. 
The survey is somewhat large (80 questions) with roughly 10 requiring the upload of 20 documents. 
The users have complained that while they prepared the answers and uploaded docs, these did not save, costing them a lot of time.

Did others encounter an issue with non-saved answers? Any suggestions/workarounds?