Great to hear about this opportunity! I've got a few questions:

• Is this position limited to certain citizenship or are you allowed to come from an arbitrary country?
• Does this position require to travel internationally? (could you list the mandatory destination countries)
• Is there a "not later than" start date (important information for people that need to quit their current job first)?

Mozilla's page says:

Please review the the guidelines for the grant program to which you are applying before submitting your registration. For assistance, please contact grants@mozillafoundation.org

Can you link to these guidelines?