Confirmed here :

“The government denounces the double taxation agreement signed on August 11, 1965 between Burkina Faso and the French Republic, which entered into force on February 15, 1967, including its amendment signed on June 3, 1971, which entered into force on October 1, 1974,” reads the press release
(...)
Phillipe Traoré, a tax expert from Burkina Faso, explained that the double taxation treaty, among other things, allows individuals and companies to avoid paying taxes on the same income in two different countries.
He believes that this measure is “very serious for French multinationals” established in Burkina, adding that “all French income derived from activities carried out on Burkinabe soil will now be taxed.”
(...)
In his opinion, this gives them a competitive advantage over all other companies operating in Burkina Faso.

I'm french and have never heard of this before, there's so much more to know.

If we consider that a double taxation would be wrong, then it should still logically be the contrary of the current situation : the benefits earned in a country have to be taxed by that country, not the country of residence.