Could you verify that you are adding the Server-side logic for the FileBrowser.ascx dialog in a custom user control, registered in the File Browser one like described here
? I am asking you that, because the described issues are usually experienced when the Server-side handlers are added directly in the FileBrowser.ascx dialog.
If this is not the case, though, could you please prepare a simple fully runnable project reproducing the issue
so we could examine the problematic configuration on our side?
Looking forward to hearing from you,
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