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Currently, when uploading a file that is too large, or has an unsupported format, it takes the necessary time to actually upload the file. After the "upload", at the end of the process (99% or so), it will generate an error message.

I guess it checks the format/size at the end of the uploading process, but maybe it's possible to move it to the beginning. This way users wouldn't wait to get the **annoying** error message