Thanks for your suggestions, Micropat.
I am not looking to make the social networks buttons appear with a local cache even if users have activated the tracking protection feature though, because it would upset them, I think.
Is there a way the data-a2a-title + data-a2a-url could show under the social networks buttons and still be displayed even when the buttons are hidden by the tracking protection, so users could still easily find what to copy and past to share the article ?