Normalization of first/last name before hashing

[CaoHaiNhi]

I have encountered an issue relating to normalization of customer information before hashing.

I sent customer information (i.e., first name) in an event (let's say Purchase) using both pixel and Conversion API. For Conversion API, I used Facebook Conversions API Tag template (https://github.com/facebookincubator/ConversionsAPI-Tag-for-GoogleTagManager).
I found that the hashed string from pixel is different from the one from Facebook Conversions API Tag template.
For example, if the first name is "a b" (notice the space between the 2 letters), the hashed string from pixel is c8687a08aa5d6ed2044328fa6a697ab8e96dc34291e8c2034ae8c38e6fcc6d65 and the one from the template is fb8e20fc2e4c3f248c60c39bd652f3c1347298bb977b8b4d5903b85055620603.
I think the reason is because pixel removes all spaces in the first name before hashing while the template only removes the leading and trailing spaces.

Could you tell me which normalization process is correct?
Does the first name after being hashed without removing the space affect Facebook retargeting?

Thank you.