How to enable docstring snippet completion for a filetype

[mdmjmsa]

Here is an example of how to enable the friendly-snippets doc snippets for a certain filetype, e.g. enabling cppdoc for cpp. How to achieve this in blink.cmp? I'm currently not having any doc snippets using the default config, and the documentation doesn't seem to mention anything about this.

[idnsunset]

Same problem, I've set opts.sources.providers.snippets.opts.extended_filetypes but still get no completion.