The flashing point regarding France's official position on Quebec separatism was General de Gaulle's visit in 1967. It is during this trip that De Gaulle made his famous "Vive le Québec libre!" speech, infuriating Lester B. Pearson's government.

A little background on the trip might help you understand why De Gaulle did such a thing. First, you have to understand that De Gaulle's presidency was in trouble, his government having barely won the 1967 legislative election. His traditional support among the right wing had been dwindling after Algeria's independance and he was facing rising students' and workers' movements on the left.

De Gaulle saw the occasion to please both the left and the right by supporting a separatist movement which could please both the nostalgics of French colonial glory and the would-be revolutionaries who felt attracted by the socialists of the FLQ or the RIN. Plus, the political cost of this - infuriating Canada - was quite low. So he planned a carefully orchestrated mise-en-scène, arriving at the port of Quebec city like Champlain (a breech of protocol, as he should have been visiting Ottawa first), and following the "Chemin du Roy" all the way to Montreal to cheering crowds. His speech would be the final camouflet to the Canadian government, and he would never reach Ottawa since it made him instantly persona non grata...

After De Gaulle's antics, subsequent French governments would take a more cold-headed approach to Quebec's separatism, a doctrine called "ni-ni" (neither-neither, for neither interference, neither ignorance), supporting the separatist movement in words, but not actively doing anything to play a part in it. This gave Quebec special access to the Francophonie organization or to programs such as the OFJQ for student exchanges, Quebec's Prime Ministers would also be greeted by the French Prime Minister during official trips and so on.

It would take until 2007 and Sarkozy's présidence for France to pull out from the "neither-neither" policy and to take an official stance for Canadian unity.

During both referendums in 1980 and 1995, securing France's approval was key to the Quebec government's strategy for the International community's approval of the results in case Ottawa contested them. Among French citizens, the approval for Quebec separatism was more anecdotical than anything else, as many (probably a majority) found it endearing that Francophones tried to fight for their independance in English North America, while a lot of these people also supported federal Europe while being hostile to nationalists at home (either Basque, Corsican, Catalan, Alsacian or Breton). Still, the Parti Socialiste in France tended to have a lot of personal links with the left-leaning Parti Québécois during the 20th Century and early 21st Century.

On the nationalist side, the accointance with French Far Right and Quebec right wing nationalists has been a thing since the 19th Century, and still exists to this day. The fascist magazine Action française had a French Canadian little brother, and many right-wingers found enthusiastic crowds on the North American side of the Atlantic during the 1930s. The same goes on today has arch-nationalist commenter Mathieu Bock-Côté is now a trending commenter on France's Fox News equivalent, CNEWS.

But the France-Quebec relationship clearly isn't only about separatism, as French immigrants are one of the main communities in the province. French people are an important part of Quebec's society, and cultural and personal bounds are many in regards to life, food, literature, music, arts, cinema and so on. Many Québécois artists made their careers or became popular in France, and their presence is a staple in TV shows and popular imagination. French people and Québécois people actually call each other "cousins", if it can give you an idea of their relationship.

On the darker side, French immigrants are often portrayed as obnoxious know-it-alls who come to Montreal to raise the rent of apartments in popular representations in Quebec while Québécois are sometimes depicted as unsophisticated and benevolent idiots who can barely speak the language in French popular culture and comedy. Still, even though there can be small dissensions, the relationship is overwhelmingly positive.

Linteau, Paul-André, Passeurs d'histoire(s) : figures des relations France-Québec en histoire du livre, Québec, Les Presses de l'Université Laval, 2010, 482 p.

Mesli, Samy. "France-Québec : l’évolution politique et sociale d’une relation privilégiée." Bulletin d'histoire politique, volume 16, number 3, spring 2008, pp. 245–254. https://doi.org/10.7202/1056184ar

Paquin, Stéphane (dir.), avec la collaboration de Louise Beaudoin, Robert Comeau et Guy Lachapelle, Les relations internationales du Québec depuis la doctrine Gérin-Lajoie (1965-2005), Québec, Les Presses de l'Université Laval, 2006, 324 p.