Visitor Visa Extn - E-Filing related question

[rk22]

I have filed I-539 thru online(E-Filing) for my MIL's visitor visa extention last Friday. Do I have send any supporting documents to USCIS ? The page related to Visitor visa extension in this website says that they will contact us if they need any supporting documents. USCIS website does not have clear info about supporting documents for e-filing. Can somebody help me with this please ?

Thanks in advance.

[immihelp]

Did you read https://www.immihelp.com/visitors-visa-extension/ ?

[rk22]

Sorry to ask you this again. In this link, I see a one line "You can also apply online at I539. You will be notified later if they need anything else." So, when I file online thru E-file, I dont need to send any documents at all ? Please let me know. Thanks for your patience.