I found conflicting statements on TSC site:
"Applications We Accept and/or Process:
NOTE EXCEPTIONS:
Forms I-131, Applications for Travel Document (Re-entry Permit or Refugee Travel Document only), are filed with the Nebraska Service Center."
"Direct Mail Cases:
Generally, the following applications and petitions must be filed, by mail, at a Service Center. However, you may be eligible to file some of these forms electronically. For more information, see Introduction to E-Filing.
I-131 Application for Travel Document. If applying for Refugee Travel Document or Reentry Permit only. To apply for Advance Parole file at the USCIS Office or Service Center where your Application for benefits is pending."