I'm using alfresco 5.2. I want to custom front-end but I don't know about files.
As you know the default/official front end is Alfresco Share .
But with use of apis- (Alfresco REST and CMIS apis) you should be able to build your own custom front end application if you have a set of functionalities you are targeting for. You can write your own react application also with bare minimum functionalities utilizing the REST apis.
Also you can investigate/analyse the new ADF which is also in progress and can create custom components as per your requirements.
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