It is not quite correct. According to a circular signed, on October 19, 2017, by Gabon’s ministers of interior and public security (in charge of decentralization and local development), and of Presidential and Public Affairs, citizens of CEMAC countries’ (Cameroon, Central Africa, Congo, Equatorial Guinea and Tchad) who hold a passport with at least a 3 months validity period, are no longer required to get a visa before they enter Gabon. This measure is only valid for stays not longer than 90 days.
This is to say that Cameroonians and the other nationals of the CEMAC who hold a passport with a validity period shorter than 3 months or those who wish to stay in Gabon for more than 3 months are required to follow the normal visa and authorization entry procedures.
Before this circular was released, only businessmen were exempt from entry authorizations for stays of less than 3 months. They could stay in Gabon for periods longer than 3 months if an authorized travel agency arranges their stay and get the required entry authorization. Those travelers were however required to justify their stays and to indicate their different contacts during their visit.
These are now the requirements to travel to Gabon: